The name Agustina is a feminine form of the Latin name Augustus, which was derived from the word "augere" meaning "to increase or augment". It is believed that the name originated in ancient Rome during the time of the Roman Empire.

The name Augustus was originally a title given to Gaius Octavius, the first Roman emperor, who ruled from 27 BC to 14 AD. He was given the title "Augustus" by the Roman Senate, which means "the revered one". The name became popular during the Roman Empire and was used by several subsequent emperors.

Agustina is the Spanish and Portuguese form of the name, and it has been in use since the Middle Ages. The earliest recorded instance of the name Agustina dates back to the 13th century, when it was used by a Spanish noblewoman named Agustina de Aragón, who lived from 1221 to 1275.

One of the most famous historical figures with the name Agustina was Agustina de Aragón, a Spanish heroine who defended the city of Zaragoza during the Peninsular War against the French in 1808. Her brave actions during the siege earned her the nickname "La Mujer Fuerte" (The Strong Woman).

Another notable Agustina was Agustina Raimunda María Sotomayor y Zorrilla, a Spanish Catholic nun who lived from 1552 to 1624. She was known for her mystical visions and was beatified by the Catholic Church in 1789.

In the 19th century, Agustina Ferrer i Vidal, a Spanish painter and educator, was born in 1835 and is remembered for her contributions to the arts and education in Spain.

Agustina de Estrada, an Argentine writer and feminist, was born in 1892 and is known for her work in promoting women's rights and education in Argentina.

Agustina Bessa-Luís, a Portuguese writer and intellectual, was born in 1922 and is considered one of the most important Portuguese writers of the 20th century. She received numerous literary awards and honors for her novels and essays.