Battle of the Alamo, KIA
Robert A. Allen was born in Virginia, about (1809) based on ages of other Defenders of the Alamo.  Robert Allen enlisted in the Texas Army. He served in the cavalry company commanded by Capt. John H. Forsyth.  
Texas Library Archives, signed by Captain John H Forsyth shows this information: Captain John H. Forsyth had 6 other men that also needed lodging, so he filled the standard paper form called C.M.S.R. #74 requisition for the owner of the establishment to file with the new provisional government, the Republic of Texas for payment for the lodging. Robert Allen's name was on this form. Form #74  Per the Comptroller of Military Service Records. The conclusive document #74 (the document which the Republic of Texas states on GLO to verify Alamo victims, and by the Daughters of the Republic of Texas state that on Record 6 men signed the document and Capt. Forsythe for board. No Records of Robert being sent out as messinger, therefore they concluded he died in the Alamo.
Robert Allen of Virginia was in the cavalry company, commanded by Captain John H. Forsyth's cavalry company. This company, commanded by Captain John H. Forsyth accompanied Lt Col. William B Travis by this cavary when he arrived at the Alamo, in late January, 1836. This man would have been one of the few who came with Col. Travis when he was assigned to help Col. Neill refurbish the Alamo with men and weapons.
Robert Allen was stationed in the Alamo garrison. He was killed with the other Defenders in the Battle of the Alamo March 6, 1836. A memorial is in San Fernando Cathedral."Find A Grave Index," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:QVK5-ZC99 : 13 December 2015), Robert Allen, 1836; Burial, San Antonio, Bexar, Texas, United States of America, The Alamo; citing record ID 50582875, Find a Grave, http://www.findagrave.com.
Note No Request for land bounties (or head right) were filed by heirs in the name of Robert Allen. This service document Muster list entitled Robert's heirs to land bounty. Robert Allen Muster list from GLO records. The Comptroller of Military Service Records #74, felt his name should be on the list of verified Defenders. They concluded his heirs should be awarded. Perhaps there were no living heirs.. This is recorded by the Daughters of the Republic of Texas, Virginia to Texas, 1835-1836, p. 138. This is all due to the above mentioned document Captain John Forsyth filled out as requisition while the 6 men were traveling to San Antonio and the Alamo. 
Robert A Allen, Alamo Defender has faded into history..
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