Anthony Quinton Keasbey (March 1, 1824 – April 4, 1895) was an American lawyer who served as United States Attorney for the District of New Jersey under seven presidents.

He was also a part of the writing of Marching Song of the First Arkansas, in addition he wrote a law book called Slavery in New Jersey.

[3] It was discovered, however, after Lincoln's death,[4] that the commission for his 1865 reappointment had not been signed, and Keasbey was thereupon appointed by President Johnson until the next session of the senate.

He thus held this position continuously from the spring of 1861 to that of 1886, a period of unbroken incumbency longer than that of any other U.S. district attorney in the Union.

He made several valuable contributions to the pamphlet and periodical literature of his day, and without seeking reputation as a poet, wrote and privately printed for many beautiful verses such as his book From the Hudson to the St.