The surname CANASTUJ is believed to have originated in Spain during the 15th century. It is likely derived from the Spanish word "canasta" which means "basket" and the suffix "-uj" which is thought to be a Catalan diminutive ending. This suggests the name may have originally referred to a basket maker or someone involved in a related trade.

One of the earliest known references to the CANASTUJ name can be found in a registry of landowners in the village of Castellón de la Plana, located in the Valencian Community region of eastern Spain. The record, dated 1487, lists a Jaume CANASTUJ as the owner of a small vineyard.

By the late 16th century, the name had spread to other parts of Spain, including the city of Seville in Andalusia. In 1592, a Antonio CANASTUJ was recorded as a member of the local guild of basket weavers. This provides further evidence of the name's connection to the basket-making industry.

In the early 17th century, the CANASTUJ name appears to have made its way to the Spanish colonies in the Americas. A Juan CANASTUJ, born in 1612 in the town of Cartagena de Indias (present-day Colombia), is listed in church records as one of the first settlers of the region.

Another notable figure with the CANASTUJ surname was María CANASTUJ, a renowned lace-maker from the city of Valencia who lived from 1745 to 1812. Her intricate lace designs were highly sought after by the Spanish nobility and her work can be found in several museums today.

During the 19th century, the CANASTUJ name gained some prominence in the field of literature. Pedro CANASTUJ (1823-1891), a writer from Barcelona, was known for his romantic poetry and his book of short stories titled "Cantos de la Tierra" (Songs of the Land) was widely acclaimed in his time.

While the CANASTUJ surname is not as common today as it once was, it remains a part of Spain's rich cultural heritage. Its origins can be traced back to the humble basket-making trade, but over the centuries, it has been associated with various professions and achievements.