The Battle of Galveston and the Emancipation Proclomation happened on the same day. The Emancipation freed alll slaves in the rebellious states. The Confederate won the Battle of Galveston. http://www.galvestonhistory.org/Battle_of_Galveston.asp
The Texas Secession Convention required all Texas leaders to take a new oath of office to the confederacy. So you couldnt be in the confederacy without oath. http://gathkinsons.net/sesqui/?p=1996