Robertson was a postmaster for the Republic of Texas and the leader of a volunteer group who aided Alexander Somervell in border disputes.

Robertson was one of the delegates who signed the Texas Order of Secession in 1861 and served as aide-de-camp to General Henry McCulloch.

Elijah Sterling Clack Robertson was born in Giles County, Tennessee, on August 23, 1820.

[5] In 1832, his father brought Robertson from Tennessee and placed him in the Mission School of St. Mary to study the Spanish language.

In return for his services, Robertson received 1,107 acres (4.48 km2; 1.730 sq mi) in Milam County.

[12] In 1842, Robertson organized a company of volunteers from Gonzales County, joining Edward Burleson at Mission Concepcion in San Antonio to oust Mexican general Ráfael Vásquez from the city.

[15] Robertson began working in a Cincinnati, Texas country store in 1845, earning $85.50 after ten months.

[15] In 1848, Robertson was a translator of Spanish deeds in the Texas General Land Office.

The jury impaneled for the subsequent trial returned a verdict of justifiable homicide.

[19] Salado College was begun on land donated by Robertson in 1859 to establish the school.

[21] In 1862, Robertson became aide-de-camp to General Henry Eustace McCulloch[19] This was the only position he held during the Civil War, but he donated a large portion of his financial resources to the cause of the Confederacy.

A suffragist active in women's rights issues, she served on the first board of regents for Texas Woman's University.