Christian Schlagle Eyster (May 19, 1814 – November 6, 1886) was an associate justice of the Colorado Territorial Supreme Court from August 11, 1866, to March 2, 1871. He was appointed by President Andrew Johnson in 1866, but because congress was not in session at the time of his appointment, the senate confirmed his appointment and he received his official commission on March 2, 1867. Eyster was President Johnson's last Colorado judicial appointment. He was a former law partner of Secretary of State William H. Seward.