Robert James Calder, soldier and public official, was born in Baltimore, Maryland, on July 17, 1810, the son of James H. and Jane E. (Caldwell) Calder. He was raised by his mother's brother, James Peckham Caldwell, after his father's death and moved to Texas from Kentucky in 1832. He joined Stephen F. Austin's army in 1835, took part as a second lieutenant in the battle of Concepción, was made third lieutenant of artillery in December, and accompanied James W. Fannin, Jr., on a recruiting expedition. In 1836 Calder joined the army at Gonzales and was elected captain of K Company, First Regiment of Texas Volunteers, which he commanded at the battle of San Jacinto. He was among those who delivered news of the battle to President David G. Burnet on Galveston Island. Calder received 640 acres of land for his service and was appointed marshal of Texas by Burnet in 1836. In 1837 he was elected sheriff of Brazoria County, a position he held for six years. One source states that "he was Brazoria sheriff during the famous Monroe Edwards contests with Dart and was swindled by Edwards out of about five thousand dollars, fees and responsibilities undertaken, while in charge of imported Africans." He was elected mayor of Brazoria in 1838 and chief justice of Brazoria County in 1844 and 1846. After moving to Fort Bend County, Calder became mayor of Richmond in 1859 and from 1866 to 1869 served as county chief justice. He later practiced law with the firm of Mitchell, Nolan, and Calder. In 1881 he officially unveiled the monument to the memory of those killed at San Jacinto. Calder married Mary Walker Douglass of Brazoria on January 3, 1837; they had six children. He died at Richmond on August 28, 1885. In 1929 the state of Texas erected a joint monument over the graves of Calder and his wife in the Richmond Masonic Cemetery.