Militants claiming to be from the Sultanate of Sulu invade Lahad Datu District, Sabah, Malaysia, beginning the Lahad Datu standoff.

The Sultanate of Sulu was a Sunni Muslim Tausūg state that ruled the Sulu Archipelago, coastal areas of Zamboanga City, and certain portions of Palawan in today's Philippines, alongside parts of present-day Sabah and North Kalimantan in north-eastern Borneo.

The Lahad Datu District is an administrative district in the Malaysian state of Sabah, part of the Tawau Division which includes the districts of Kunak, Lahad Datu, Semporna and Tawau. The capital of the district is in Lahad Datu Town.

Sabah is a state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah has land borders with the Malaysian state of Sarawak to the southwest and Indonesia's North Kalimantan province to the south. The Federal Territory of Labuan is an island just off Sabah's west coast. Sabah shares maritime borders with Vietnam to the west and the Philippines to the north and east. Kota Kinabalu is the state capital and the economic centre of the state, and the seat of the Sabah State government. Other major towns in Sabah include Sandakan and Tawau. The 2020 census recorded a population of 3,418,785 in the state. It has an equatorial climate with tropical rainforests, abundant with animal and plant species. The state has long mountain ranges on the west side which forms part of the Crocker Range National Park. Kinabatangan River, the second longest river in Malaysia runs through Sabah. The highest point of Sabah, Mount Kinabalu is also the highest point of Malaysia.

The 2013 Lahad Datu standoff, also known as the Lahad Datu incursion or Operation Daulat, was a military conflict in Lahad Datu, Malaysia. The conflict began on 11 February, when 235 militants arrived in Lahad Datu by boat, and ended on 24 March. The militants, self proclaimed as "Royal Security Forces of the Sultanate of Sulu and North Borneo", were sent by Jamalul Kiram III, a claimant to the throne of the Sultanate of Sulu.