Henley-on-Thames is a town on the north side of the River Thames in south Oxfordshire, England, about 10 miles downstream and north-east from Reading, 10 miles upstream and west from Maidenhead. It is located near the corner between the counties of Oxfordshire, Berkshire and Buckinghamshire.

Henley does not appear in Domesday Book of 1086 often it is mistaken for Henlei in the book which is in Surrey.

The first record of medieval settlement dates to 1179, when it is recorded that King Henry II “had bought land for the making of buildings”. King John granted the manor of Benson and the town an manor of Henley to Robert Harcourt in 1199. A church is first mentioned at Henley in 1204. In 1205 the town received a pavage grant, and in 1234 the bridge is first mentioned. In 1278 Henley is described as a hamlet of Benson with a Chapel. It is probable that the street plan was established by the end of the 13th century.

As a demesne of the crown it was granted to John de Molyns, in 1337 whose family held it for about 250 years. It is said that members for Henley sat in parliaments of Edward I and Edward III, but no writs have been found to substantiate this.

The existing Thursday market, it is believed, was granted by a charter of King John. A market was certainly in existence by 1269, however, the jurors of the assize of 1284 said that they did not know by what warrant the earl of Cornwall held a market and fair in the town of Henley. The existing Corpus Christi fair was granted by a charter of Henry VI.

By the beginning of the 16th century the town extended along the west bank of the Thames from Friday Street in the south to the Manor, now Phyllis Court, in the north and took in Hart Street and New Street. To the west it included Bell Street and the Market Place.

Henry VIII. having granted the use of the titles "mayor" and "burgess", the town was incorporated in 1568 by the name of the warden, portreeves, burgesses and commonalty.

Henley suffered from both parties in the Civil War. William III on his march to London in 1688 rested here and received a deputation from the Lords. The period of prosperity in the 17th and 18th centuries was due to manufactures of glass and malt, and to trade in corn and wool.

Henley-on-Thames owes much to its location and port that supplied London with timber and grain.

Henley Bridge is a five arched bridge across the river which was built in 1786. The church of St. Mary is located nearby and features a tower built in the 16th century. About a mile upstream of the bridge is Marsh Lock.

In the vicinity of Henley, there are several notable private buildings:

Fawley Court is a red-brick building designed by Christopher Wren. Greenlands which took its present form when owned by W. H. Smith and is now home to Henley Management College