The Constitution of the Republic of Texas was the supreme law of Texas from 1836 to 1845. On March 2, 1836, Texas declared itself an independent republic because of a lack of support in the United States for the Texas Revolution. The declaration of independence was written by George Childress and modeled after the United States Constitution. Lorenzo de Zavala helped in the drafting of the Constitution of the Republic of Texas by personally designing its flag and serving as vice president. A copy of the Constitution of the Republic of Texas was included with the declaration of independence. The constitution borrowed language from the US Constitution and the constitutions of several southern states. It formed a unitary republic, rather than the federal republic as defined in the US Constitution. The President of the Republic of Texas had a three-year term and could not serve another consecutive term, which was based on provisions in the Mexican Constitution. The Texas Constitution also protected the right to own slaves and prohibited "Indians" and "Africans" from living freely in the country or from becoming Texan citizens. History Constitutional Convention and ratification A constitutional convention began after the declaration of independence, and an interim government was put into place. The convention adopted a document on March 16, 1836 and adjourned the next day. Because of the defeat of Santa Anna at San Jacinto on April 22, 1836, war with Mexico was over. When June came around, the Republic of Texas had de facto independence as it was unrecognized by Mexico, but Mexico was unable to bring the Republic to an end. Interim President Burnet, on July 23, 1836 called for elections to ratify the constitution and to decide if Texas should pursue annexation into the United States. The elections were to occur on the first Monday of September. After the elections, the constitution was ratified, Sam Houston was elected president, and Mirabeau Buonaparte Lamar became his vice-president, and the seeking annexation was decided. Statehood On March 1, 1845, the United States enacted a congressional joint resolution to propose the annexation of Texas to the United States (Joint Resolution for annexing Texas to the United States, Joint Resolution 8, enacted March 1, 1845, ). On June 23, 1845, the Texan Congress accepted the US Congress joint resolution and consented to President Anson Jones's call for a convention to be held on July 4, 1845. A