|Title||Lord of Horn Hill|
Alan supported Queen Rhaenyra Targaryen and the blacks. Joined by Lord Owen Costayne and Ser Alan Beesbury, Lord Tarly trapped Lord Ormund Hightower's forces along the banks of the Honeywine between them and another army of blacks led by Lord Thaddeus Rowan and Tom Flowers. Ormund's lines started to crumble and defeat seemed all but a forgone conclusion. However, Prince Daeron Targaryen attacked on his dragon, Tessarion, turning the battle for the greens. Alan was captured after the Battle of the Honeywine.
The relation between Alan and Lord Donald Tarly, the head of the house during the reign of King Viserys I Targaryen, is unknown. As neither of Donald's daughters succeeded him, it is likely that Alan was Donald's son.
- Fire & Blood, The Dying of the Dragons - The Red Dragon and the Gold.