The Carpenter Agreement (1915): What Was Terminated and What Was Preserved

Why this instrument matters

The Carpenter Memorandum Agreement of 22 March 1915 is the single document under which the political sovereignty of the Sulu Sultanate was formally terminated. Every other instrument in the Sulu legal corpus — the 1878 Sabah arrangement, the 1899 Bates Treaty, the various Spanish-Sulu agreements of the 19th century — either failed to terminate sovereignty or addressed peripheral matters. The Carpenter Agreement is the operative terminus.

It is also one of the most carefully drafted documents in the U.S. colonial legal corpus, because it had to do something legally novel: terminate the political sovereignty of a recognized polity while preserving its religious-customary authority in the same instrument. This entry treats the document as the instrument it actually was, distinguishing what it did from what it has often been claimed to have done.

This is a companion to The Treaties That Ended a Sovereignty, which places the Carpenter Agreement within the wider Sulu arc.

The signing context

The 1899 Bates Treaty had been abrogated in 1904. The intervening eleven years had produced the Bud Dajo killings (March 1906), the Bud Bagsak operation (June 1913, with similar though smaller-scale civilian casualties), and continuous low-intensity conflict between U.S. forces and Sulu communities that did not accept direct military administration.

By 1913, U.S. policy in the Philippines was shifting under the Wilson administration. The new Governor-General Francis Burton Harrison (1913–1921) inaugurated the “Filipinization” policy — the progressive transfer of administrative authority from American to Filipino civil officials, in preparation for eventual independence. In the southern Philippines, this required dismantling the Moro Province military government and replacing it with civil administration under the Department of Mindanao and Sulu.

Frank W. Carpenter was appointed Governor of the new Department in 1914, with explicit instructions to integrate the Moro territories into civil administration on terms that would not require continuous military operations. The political problem he inherited: as long as the Sultanate persisted as a political sovereign, civil integration was conceptually obstructed; but any attempt to terminate the Sultanate by force would reproduce the conditions that had produced Bud Dajo and Bud Bagsak.

Carpenter’s solution was a negotiated agreement that would terminate the Sultanate’s political authority while preserving its religious and customary authority in a form acceptable to the Sultan and to the Sulu communities whose acceptance the U.S. needed.

The signing

On 22 March 1915, at Zamboanga, Sultan Muhammad Jamalul Kiram II and Governor Frank W. Carpenter signed the Memorandum Agreement. Witnesses included senior U.S. officials and Sulu datus.

The text is brief — a memorandum, not a treaty — and is structured around three operative provisions:

Provision 1. The Sultan acknowledges that “all rights of sovereignty exercised by the Sultan of Sulu in the Sulu Archipelago are now vested in the Government of the United States of America.”

Provision 2. The Sultan “shall be recognized as the titular spiritual head of the Mohammedan Church in the Sulu Archipelago, with the same authority over religious matters as that exercised by other religious leaders.”

Provision 3. The U.S. government shall provide for the Sultan and his immediate dependents an annual allowance, and shall preserve his properties and customary rights.

The agreement does not call itself a treaty — deliberately, since the U.S. position by 1915 was that it could not enter treaty relations with what it had reclassified as a domestic indigenous polity. The choice of “memorandum” allowed Carpenter to obtain what was needed without re-opening the international-law questions the Bates Treaty had implicitly raised.

Source-criticism card: the Carpenter Agreement (1915)

Custody chain: Original in U.S. War Department / Bureau of Insular Affairs files; reproductions in U.S. official compilations and in Philippine government archives.

Tier: A — primary legal instrument, contemporaneous, signed and witnessed.

Reliability — that signing occurred: HIGH.

Reliability — text as evidence of operative scope: HIGH for the political-religious distinction, which is explicit on the face of the document.

Reliability — text as evidence of Sulu-side intent: MEDIUM. The Sultan signed; what the agreement was understood to mean by the broader Sulu community is a separate question, addressable only through subsequent conduct.

Use guidance: Cite as the operative terminus of Sultanate political sovereignty. Always specify political — the agreement explicitly preserves religious and customary authority, and never extinguishes the lived sovereignty of the Sulu peoples.

What was terminated

The Carpenter Agreement effected the termination of the Sultanate’s political sovereignty in the international-law sense:

The capacity to enter treaty relations with foreign sovereigns
The capacity to maintain armed forces independent of U.S. authority
The capacity to administer secular law independent of U.S. courts
The capacity to collect tribute, levies, or taxes independent of U.S. fiscal authority
The capacity to control foreign trade independent of U.S. customs authority

These were precisely the powers that the Sultanate had exercised, in some form, from its founding in the 15th century through 1915. Their termination is what makes 1915 the operative terminal date for the Sultanate as a political institution.

The annual payment of P5,700 (later adjusted) provided to the Sultan was characterized in the agreement as an allowance, not as a tribute or sovereignty fee — terminology designed to remove any implication that U.S. payments acknowledged residual sovereign claims.

What was preserved

The Carpenter Agreement explicitly preserved:

The Sultan’s status as titular head of the Mohammedan Church in the Sulu Archipelago — i.e., his religious authority over the Muslim community of Sulu
The recognition of customary law (adat) and Islamic personal-status law in matters of marriage, inheritance, divorce, and intra-community dispute resolution
The Sultan’s personal properties and customary rights
The structure of datu authority under customary law, subject to U.S. civil oversight

This preservation was not nominal. From 1915 forward, U.S. and later Philippine state policy continued to recognize Islamic personal-status law for Muslims in the Sulu region, and the Sultan continued to exercise religious and customary authority within the Tausug community. The institutional thread runs unbroken from 1915 through the Code of Muslim Personal Laws of the Philippines (1977) to the Bangsamoro Organic Law (2018) and the present Bangsamoro Autonomous Region in Muslim Mindanao.

What could not be terminated

The Carpenter Agreement, like every other instrument before it, could not reach the lived sovereignty of the Sulu peoples. It could and did terminate the Sultanate as a political institution. It could and did transfer political-administrative authority to the U.S. government. It did not, and could not, alter:

The customary authority of datus within their kin-group communities
The internal religious life of Tausug, Sama-Bajau, Yakan, and other Sulu communities
The household-level economic and social organization of those communities
The capacity of communities to govern their own internal affairs through traditional mechanisms
The continuity of memory, identity, and self-understanding among Sulu peoples as Sulu peoples

This is the through-line of the entire Sulu arc, made explicit in Story 5: colonial instruments target the apex; the substrate continues. The Carpenter Agreement is the cleanest legal demonstration of this distinction, because the U.S. drafters were sophisticated enough to recognize the limit of what their instrument could accomplish and structured the document accordingly. They terminated what they could terminate. They acknowledged that they could not terminate what they could not.

The 110-year afterlife

The provisions of the Carpenter Agreement have remained operative, in modified form, through three sovereign successions:

U.S. colonial period (1915–1946): The Department of Mindanao and Sulu administered the secular affairs; the Sultan retained religious-customary authority.
Republic of the Philippines (1946–present): The Republic inherited U.S. sovereignty over Sulu; Islamic personal-status law was codified in the Code of Muslim Personal Laws (1977); the Sultan’s religious-customary status continues to be recognized in practice though contested in form.
Bangsamoro Autonomous Region (2019–present): The current autonomy framework is, in important respects, the contemporary institutional realization of what Carpenter preserved in 1915 — the structural recognition that the Sulu peoples possess a distinct legal-political identity that cannot be fully dissolved into the unitary Philippine state.

This continuity is what makes the Carpenter Agreement, despite being a memorandum and not a treaty, one of the most consequential documents in Philippine constitutional history. It established the principle that Muslim Mindanao and the Sulu archipelago carry a legal personality that the Philippine state does not extinguish — a principle that has shaped every subsequent legal framework addressing the region.

What can honestly be said

Anchored: The Carpenter Agreement was signed on 22 March 1915 and effected the termination of the Sultanate’s political sovereignty while preserving the Sultan’s religious-customary authority.
Anchored: The agreement’s structural distinction between political and religious-customary authority has been preserved through every subsequent Philippine legal-institutional framework addressing the region.
Probable: The drafters understood the limit of what the instrument could accomplish — i.e., that lived sovereignty of communities was beyond legal reach — and structured the document to do what it could do without overreaching.
Contested: Whether the Sultan possessed authority under Sulu customary law to terminate the Sultanate’s political sovereignty by his individual signature, or whether such termination would have required broader community consent that was not obtained.

Quarantined Claims

Applying the framework laid out in Story 1:

QUARANTINED: That the Carpenter Agreement “ended the Sulu Sultanate.” It terminated the Sultanate’s political sovereignty. The Sultanate as a religious-customary institution continues to exist; the Sulu peoples’ lived sovereignty was never on the table.
QUARANTINED: That the Carpenter Agreement effected a complete absorption of Sulu into the Philippine state. Its preservation of religious-customary authority created the legal-institutional foundation on which Bangsamoro autonomy claims and frameworks have continuously rested.
QUARANTINED: That the present Bangsamoro Autonomous Region is a 21st-century novelty unrelated to the historical Sultanate. It is the contemporary institutional expression of the legal-religious-customary continuity that the 1915 agreement explicitly preserved.
QUARANTINED: That the Sultan’s signature in 1915 was procedurally adequate to alienate community-level sovereignty. The agreement could and did transfer the apex political authority the Sultan held; it could not and did not transfer authorities that did not flow through the Sultan in the first place.
QUARANTINED: That the annual allowance was a sovereignty fee or tribute. It was structured precisely to avoid that characterization, in deliberate contrast to the Bates Treaty’s tribute-resembling payment scheme.

Primary source: The Carpenter Memorandum Agreement (Memorandum of Agreement Between the Government of the Department of Mindanao and Sulu and His Highness the Sultan of Sulu, signed at Zamboanga, 22 March 1915); U.S. Bureau of Insular Affairs files on the Department of Mindanao and Sulu; correspondence of Carpenter, Harrison, and the Wilson administration on Filipinization. Secondary: Peter Gowing, Mandate in Moroland: The American Government of Muslim Filipinos, 1899–1920 (1977); Samuel K. Tan, The Filipino Muslim Armed Struggle, 1900–1972 (1977); Cesar Adib Majul, Muslims in the Philippines (1973); Patricio Abinales, Making Mindanao: Cotabato and Davao in the Formation of the Philippine Nation-State (2000); Thomas McKenna, Muslim Rulers and Rebels: Everyday Politics and Armed Separatism in the Southern Philippines (1998); Soliman M. Santos Jr., The Moro Islamic Challenge: Constitutional Rethinking for the Mindanao Peace Process (2001); Bangsamoro Organic Law (Republic Act No. 11054, 2018) for the contemporary institutional descent. Internal cross-references: see “The Treaties That Ended a Sovereignty” for the full arc, “The Bates Treaty” for the predecessor instrument, and “The 1878 Sulu Instrument” for the contemporaneous international dimension.