Amasa Cobb (September 27, 1823 - July 5, 1905) was a Republican Wisconsin politician. Born in Crawford County, Illinois in 1823, he moved to the Wisconsin Territory in 1842 and mined for lead. He served in the Mexican-American war as a private. After the war he studied law, passed the bar and set up practice in Mineral Point, Wisconsin. He was a district attorney from 1850 to 1854, then was elected to the Wisconsin State Senate in 1855, serving until 1856. During his term he was also the adjutant general of Wisconsin from 1855 to 1858. He became a member of the state assembly in 1860 and served as speaker in 1861.
He joined the Union army in 1861 as a colonel in the Fifth Wisconsin Infantry, later becoming the colonel of the Forty-Third Wisconsin Infantry on September 29, 1864. Was brevetted brigadier general.
During the civil war, he was elected to the 38th congress from Wisconsin, being reelected to the 39th, 40th, and 41st Congresses (1863-1871).
He moved to Lincoln, Nebraska where he started to practice law again. He was appointed mayor of Lincoln in 1873, and then became associate justice of the Nebraska state supreme court in 1878 to 1892. The last four year, from 1888 to 1892 he served as Nebraska's chief justice. He then died in Los Angeles in 1905.
Preceded by: Samuel W. Little Mayor of Lincoln 1875 - 1876 Succeeded by: Robert D. Silver, Jr.