Born on October 24, 1809, in Stratham, New Hampshire,[1] Clark attended the common schools Hampton Academy (now New Hampton School) and Union College in Schenectady, New York.

[1] He was admitted to the bar and entered private practice in Epping, New Hampshire from 1836 to 1839.

[2] He was reelected in 1861, and served from June 27, 1857, to July 27, 1866, when he resigned to accept a federal judicial post.

[2] Clark was nominated by President Andrew Johnson on July 27, 1866, to a seat on the United States District Court for the District of New Hampshire vacated by Judge Matthew Harvey.

[1] He was confirmed by the United States Senate on July 27, 1866, and received his commission the same day.