In 1114, King Henry I gave Ellesmere to William Peverel as a part of the Maelor, which included Overton and Whittington at that time.

His descendants retained Ellesmere until apparently the late 1140s when the lordship was acquired, probably by force, by Madog ap Maredudd of Powys.

In mid-April 1205, Llywelyn the Great married Joan, Lady of Wales illegitimate daughter of King John and Ellesmere was given to them as a wedding gift.

Llywelyn's mother was Marared (Margaret), daughter of Madog ap Maredudd, Prince of Powys.

There is evidence that, after her first husband Iorwerth's death, Marared married in the summer of 1197, Gwion, the nephew of Roger Powys of Whittington Castle.

Ellesmere was ordered to be attacked by King Henry III in 1231, but Llywelyn retained control of the lordship until his death in 1240.

In 1241 King Henry III ordered John le Strange to repair the wooden castle of Ellesmere.

By 1294, the preceptory of Dolgynwal (Ysbyty Ifan, Denbighshire, on the banks of the River Conwy) had been united with Halston, which was subsequently the administrative centre for all Knights Hospitaller estates in North Wales.

Dolgynwal, which had been founded c. 1190, had acquired Ellesmere Church, its most substantial property, from Llywelyn the Great in 1225 In 1435, Griffin Kynaston, Seneschal of the Lordship of Ellesmere, (born at Stocks of landed gentry – descended from the princes of Powys), gave evidence at Shrewsbury to confirm the age of John Burgh, Lord of Mowthey, sponsored by Lord John Talbot, 1st Earl of Shrewsbury, Lieutenant of Ireland.

A patron of the arts, in 1848 he purchased at auction for 355 guineas from the estate of Richard Temple-Grenville, 2nd Duke of Buckingham and Chandos, the only known (or suspected) portrait of William Shakespeare in existence.

These gardens were given to the people of Ellesmere by Lord Brownlow who was heavily involved in the Edward VIII abdication crisis of 1936.

In 1806 a July Fair was introduced (in addition to the regular fairs in February, April, August and November) this being for the sale of "horned cattle, horses, pigs, sheep, leather, grain, butter, cheese, wool, bacon, hops, and every other produce of land".

An artificial island in the Mere was constructed in 1812 from soil dug out during the making of the gardens at Ellesmere House.

[11] However, the section from Whitchurch to Welshpool (Buttington Junction), via Ellesmere, Whittington, Oswestry and Llanymynech, closed on 18 January 1965 in favour of the more viable alternative route via Shrewsbury.

Lakelands Academy provides state-paid education for boys and girls in the 11–16 age range (for whom schooling is compulsory) and its former pupils include Luke Preston.

A short distance outside the town is Ellesmere College, a public (i.e., private) boarding school founded in 1884 by Canon Nathaniel Woodard for sons of the middle classes.

[15] [16] The town also has a semi-professional football club, Ellesmere Rangers FC, who play their home games at Beech Grove.