The surname Milia is of Italian origin, with roots tracing back to the medieval era. It is believed to have derived from the Latin word "milium," which means "millet" or "small grain." This suggests that the name may have initially been associated with individuals involved in the cultivation or trade of grains like millet.

The earliest known record of the Milia name appears in the Codice Diplomatico Longobardo, a collection of historical documents from the Lombard period in Italy, dating back to the 8th century. In these documents, the name is sometimes spelled as "Miglia" or "Milie," indicating regional variations in pronunciation and spelling.

One of the earliest known bearers of the Milia name was Giovanni Milia, a nobleman from the town of Sorrento, near Naples, who lived in the 13th century. Records indicate that he held significant land holdings and played a role in local politics during that time.

In the 14th century, the Milia family established roots in the region of Tuscany, particularly in the cities of Florence and Siena. Matteo Milia, born in 1312, was a renowned artist and architect who contributed to the design and construction of several churches and public buildings in Florence.

During the Renaissance period, the Milia name became associated with the arts and academia. Lucrezia Milia, born in 1492 in Venice, was a celebrated poet and scholar whose works were widely acclaimed throughout Italy. Her contemporaries praised her for her intellect and literary prowess.

In the 17th century, the Milia family expanded its influence to other parts of Italy, including the region of Piedmont. Pietro Milia, born in 1624 in Turin, was a respected jurist and legal scholar who served as a judge in the Savoy court.

Another notable bearer of the Milia name was Carlo Milia, born in 1758 in Naples. He was a renowned composer and musician who served as the court composer for the Kingdom of Naples during the late 18th century. His compositions, particularly his operas and chamber music, were widely performed across Europe.

The Milia surname has also been associated with several place names in Italy, such as Milia San Pietro and Milia Santa Maria, both located in the province of Messina, Sicily. These place names likely derived from the surname itself, indicating the presence of Milia families in those areas.