The name Mildred has its roots in the Germanic languages, deriving from the Old English words "milde" meaning gentle or merciful, and "þræd" meaning strength or might. It was a popular name among the Anglo-Saxons and the earliest recorded spelling was "Mildriþ" in the Domesday Book of 1086, a survey commissioned by William the Conqueror.

The name is believed to have been introduced to England by German missionaries and it gained popularity during the Middle Ages. One of the earliest notable bearers of the name was Saint Mildred, a 7th-century abbess of the monastery on the Isle of Thanet in Kent, England. She was revered for her piety and charity, and her feast day is celebrated on July 13th.

Another prominent figure in history associated with the name Mildred was Mildred, Lady Burghley (1528-1589), an English noblewoman and the wife of Lord Burghley, who served as Lord Treasurer under Queen Elizabeth I. She was known for her intelligence and influence in political circles during the Elizabethan era.

In the 19th century, Mildred was a fashionable name among the upper classes in Britain and the United States. One notable bearer of the name was Mildred Barnes Bliss (1879-1969), an American philanthropist and co-founder of the Dumbarton Oaks Research Library and Collection in Washington, D.C. She was a prominent figure in the arts and humanities.

Another famous Mildred was Mildred Elizabeth Gillars (1900-1988), an American broadcaster who earned the nickname "Axis Sally" for her propaganda broadcasts during World War II, aimed at undermining the morale of Allied forces. She was convicted of treason in 1949 and served a 12-year prison sentence.

Mildred Ella Didrikson Zaharias (1914-1983) was an American athlete and one of the greatest female athletes of the 20th century. She excelled in multiple sports, including golf, basketball, and track and field, and was known for her exceptional skill and determination.

While the name Mildred was popular in the early 20th century, its usage has declined significantly in recent decades, though it remains a part of the rich tapestry of English-language names with a fascinating historical legacy.