Pilar is a feminine given name of Spanish origin, derived from the Latin word "pila" meaning "pillar" or "column." The name first emerged in the Middle Ages and was initially used as a religious title or an epithet for the Virgin Mary, who was seen as a pillar of strength and support for the Christian faith.

The name is closely associated with the famous Catholic pilgrimage site, the Basilica of Our Lady of the Pillar in Zaragoza, Spain. According to tradition, the Virgin Mary appeared to St. James the Great in the year 40 AD, standing atop a pillar and encouraging him to spread Christianity in the Iberian Peninsula. This legend contributed to the widespread popularity of the name Pilar among Spanish Christians.

One of the earliest recorded uses of the name Pilar dates back to the 13th century, when Pilar de Aragón, a Spanish noblewoman, was born in 1220. She was a member of the powerful House of Aragon and played a significant role in the political affairs of her time.

In the 16th century, Sor Juana Inés de la Cruz, a renowned Mexican nun, scholar, and poet, was born as Juana Inés de Asbaje y Ramírez de Santillana in 1651. Her mother's name was Pilar de Asbaje, contributing to the spread of the name in the Americas.

Another notable figure bearing the name Pilar was Pilar Primo de Rivera, a Spanish politician and the founder of the Falange Femenina, the women's branch of the Falange political movement in Spain. She was born in 1907 and played a significant role in promoting the ideals of the Falange during the Spanish Civil War and the Franco regime.

Pilar Lorengar, a Spanish operatic soprano, was also a notable bearer of the name. She was born in 1928 and had a successful international career, renowned for her performances in operas by composers such as Mozart, Verdi, and Puccini.

Pilar Urbano, a Spanish journalist and author, was born in 1940. She is known for her biographies of prominent figures, including Mother Teresa of Calcutta and King Juan Carlos I of Spain.

While the name Pilar has its roots in Spanish and Latin American cultures, it has also gained popularity in other parts of the world, particularly in countries with strong Spanish or Catholic influences.