The surname Wader originates from England and can be traced back to the medieval period. The name is believed to have first appeared in areas surrounding the Anglo-Saxon settlements, possibly derived from an old English occupational term or a locational name. One theory suggests that the name could be linked to the Old English word "wadan," meaning "to go" or "to wade", which would make sense in regions where marshlands or rivers were prominent.

Early references to the surname can be found in medieval manuscripts and tax records. For example, in the Subsidy Rolls of Yorkshire dated 1379, a Thomas Wader is recorded. This indicates that the surname was in use among commoners during the late 14th century and was possibly tied to agricultural or water-related occupations, given the meaning of the root word.

One of the earliest recorded instances of this surname appears in the Domesday Book of 1086, where a landholder named Walter Wader was documented. This suggests that the name had established some social significance by the Norman Conquest. The Domesday Book, commissioned by William the Conqueror, was an extensive survey of lands and resources in England, highlighting individuals of note at the time.

Another significant historical figure bearing the surname was John Wader, who served as a steward to a noble family in the late 15th century. Records from the Staffordshire County archives mention John Wader in legal documents dated 1492, suggesting that members of the Wader family were involved in administrative roles during this period.

In the 17th century, we find reference to Elizabeth Wader born in 1615 and mentioned in parish registers in London. Her marriage to Thomas Smith in 1640 is recorded in St. Giles’ church archives, providing evidence of the name's continued presence in urban areas.

Famous individuals with the surname Wader include Walter de Wader, who was a 13th-century knight known for his participation in the Crusades. His name appears in military records dating to 1248, where he was recognized for his service to King Louis IX of France.

Another notable figure is Richard Wader, who was active in early American colonial history. Born in 1695, Richard was involved in the settlement of Massachusetts and is noted for his contributions to the local community as recorded in town meeting notes from 1732.

In the later half of the 18th century, Benjamin Wader, born in 1742, was a prominent merchant known for his trade relations in the ports of Liverpool. His business dealings are well-documented in shipping logs and letters from that era, indicating the family’s expansion into commerce and trade.

Throughout history, the surname Wader has thus been associated with a variety of social roles, from landholders and knights to stewards, settlers, and merchants. While the Occupational or locational roots of the name suggest humble beginnings, the historical records reflect a name that evolved and adapted through various social and economic changes over centuries.