James Hamilton Abercorn , 1st Earl of Abercorn (c. 1575-1618), was the eldest son of Claud Hamilton, Lord Paisley (4th son of James, 2nd earl of Arran, and duke of Chatelherault), and of Margaret, daughter of George, 6th Lord Seton. He was made sheriff of Linlithgow in 1600, received large grants of lands in Scotland and Ireland, was created in 1603 baron of Abercorn, and on the 10th of July 1606 was rewarded for his services in the matter of the union by being made earl of Abercorn, and Baron Hamilton, Mount Castle and Kilpatrick. He married Marion, daughter of Thomas, 5th Lord Boyd, and left five sons, of whom the eldest, baron of Strabane, succeeded him as 2nd earl of Abercorn. He died on the 23rd of March 1618. The title of Abercorn, held by the head of the Hamilton family, became a marquessate in 1790, and a dukedom in 1868, the 2nd duke of Abercorn (b. 1838) being a prominent Unionist politician and chairman of the British South Africa Company.

Original text from From 1911 Encyclopaedia Britanica