After Texas seceded from the Union, the 1861 constitution was drafted to transfer Texas statehood from the United States of America to the Confederate States of America. This constitution did not greatly alter the 1845 constitution, but rather altered references from the United States of America to the Confederate States of America and required elected officials to take an oath of loyalty to the Confederate States of America.
The Constitution of the Confederate States of America, the Ordinances of the Texas Convention, and an Address to the People of Texas: Printed by Order of the Convention of the Senate. Austin: Printed by John Marshall, state printer, 1861. Winkler-Friend 189.