Clare is a market town on the north bank of the River Stour, 14 miles (23 km) from Bury St Edmunds and 9 miles (14 km) from Sudbury. Clare won Village of the Year in 2010 and Anglia in Bloom award for Best Large Village 2011 for its floral displays in 2011.

In March 2015, The Sunday Times and Zoopla placed Clare amongst the top 50 UK rural locations, having "period properties and rich history without the chocolate-box perfection – and the coach trips".

Clare and its vicinity has evidence of human habitation throughout prehistory, through the Norman Conquest, to the present day. The town hosts Stour Valley Community School, one of the first free schools established by the government,[3] opened in September 2011.

There are some 24 other pre-Iron Age structures in the parishes around Clare. An Iron Age pot was found embedded in the river bank, half a mile east of Clare. Together with an iron spearhead, they are held in The Ancient House. Iron Age coins have also been found, one from the Belgic Trinovantes tribe.

In 2009 during a recent rebuilding programme at Clare Community Primary School, postholes of a late Bronze/Early Iron Age structure were located, with an associated ring ditch. This supports the view that Clare Camp with its double ditches, one of the most impressive of its kind in Suffolk, is from that period; with an area of 2.9 hectares, it is second only to Burgh Castle. It is now entered into the Atlas of Hillforts.

Clare was on the outer borders of the Trinovantes territory, just south of the Iceni. The camp probably marks the first permanent settlement in the area.

The Domesday Book records that the lands around Clare belonged to a Saxon thane, Aluric (or Aelfric), son of Wisgar (or Withgar) and that he gave them to St John, probably creating in Clare a collegiate church under Edward the Confessor.

William the Conqueror re-granted the land to one of his closest supporters in the Norman Conquest of 1066, Richard fitz Gilbert of Bienfaite, Count of Brionne, the son of one of his cousins, along with 170 other manors, 95 of them in Suffolk.

This huge feudal barony became known as the Honour of Clare. Richard became known as "Richard de Clare" (or "of Clare") after he made the castle of Clare the caput of his feudal barony, that is to say his administrative centre. He also held a large manor in Tonbridge, Kent where he built a motte and bailey castle of a very similar size to Clare Castle. Clare Castle is first recorded in 1090.

His son Gilbert de Clare gave the church in the castle to the Benedictine Bec Abbey in Normandy. Gilbert and his brother were present with Prince Henry when King William II was shot dead by an arrow fired by Walter Tyrell, Gilbert's steward. Tradition is strong that the Clares had staged an assassination. King Henry I was crowned three days later.

In 1124 Gilbert's son Richard de Clare removed the Benedictines to a new foundation in Stoke-by-Clare, the origin of today's Stoke College.

In 1140 Richard's son Gilbert de Clare was given the title of Earl of Hertford by King Stephen. He joined the revolt against the king but later returned to support him.
Richard de Clare, 3rd Earl of Hertford and his son Gilbert were two of the 25 barons appointed as guardians to Magna Carta of 1215. Richard married the heiress of the Earl of Gloucester, whose sister had been the first wife of King John.

Gilbert de Clare, 4th Earl of Hertford inherited the title and vast estates of the Earl of Gloucester. It was his son, Richard who brought the Augustinian Friars to Clare to found the mother house in England in 1248.

The wealthiest of the Clare family was Gilbert de Clare, 7th Earl of Gloucester ('the Red'). He sided with Simon de Montfort and attended Montfort's Parliament, but then fell out with Montfort and fought alongside Prince Edward at the Battle of Evesham, when Montfort was killed. He seized London and held it against King Henry III. After King Edward I's accession, he married Joan of Acre in 1290, the king's daughter. He surrendered his lands to the king and was re-granted them. He held land in 26 English counties and also estates in Wales, including Caerphilly, Usk and Tintern. This era represented the high point of the family as a major force in English history.

On his death in 1295, his wife Joan remarried one of his household knights and began new works at Clare Priory. She was buried in the Chapel of St Vincent which she herself had founded in 1307. The funeral was one of the major public events in Clare's history, attended by royalty and nobility, including her brother King Edward II.

Her son Gilbert was the last male de Clare. At the battle of Bannockburn in 1314, he was accused of cowardice and treason when he recommended holding the better ground rather than attacking Bruce's densely packed pike walls. Against his better judgement he led the charge and was killed. One of Gilbert's sisters, Elizabeth de Burgh eventually came into the property of Clare, and she endowed what would become Clare College, Cambridge.
William de Burgh was Elizabeth's son by her first husband, John de Burgh, next in line to the Earldom of Ulster. He was assassinated in Carrickfergus in 1333 by his Irish cousins.

His daughter Elizabeth was married to the third son of Edward III. Her husband Lionel thereby came into the Clare inheritance and became the Duke of Clarence. Chaucer the poet was at one time a page to him. After Elizabeth's death in 1360, he married the Count of Milan's daughter. There were wild rumours he was about to become King of Italy, but he died near Pavia a few months after his marriage. Following his last wish, his heart and bones were brought back to Clare for burial beside his first wife.

The title of Clarenceux King of Arms, an heraldic officer, is also derived from Clare or Clarence.
The estate passed into the hands of the Mortimers, the Earls of March. The castle began to fall into disrepair from this time. The last descendant was Edward V, one of the two Princes in the Tower. Henry VII took over Clare borough and manor. Henry VIII gave them to each of his wives in turn, Katherine of Aragon leasing the common to the poor of Clare.