TONIGHT Bournemouth’s St Peter’s Church will be floodlit in honour of the town’s founder Lewis Tregonwell, who lies in the churchyard.

Two hundred years ago tonight Cornishman Tregonwell and his wife went to bed for the first time in their new Bournemouth home, The Mansion. Their house, now the Royal Exeter Hotel in Exeter Road, is still known as the town’s first house.

Building work had taken two years from June 1810, when Tregonwell brought his wife Henrietta to see the sandy chine carrying the River Bourne down from Canford Heath to the sea.

He knew the area from the six years he spent patrolling as captain of the Dorset Rangers on alert for invasion.

His wife loved the valley, and for her he built the house.

It was not the very first building but it was the first private residence. An existing structure was the Tapps Arms in Old Christchurch Road, which was just a year old when the couple had lunch there on that first visit. On Friday April 24, 1812, the couple set out in the morning from their house in Cranborne for their new holiday home with a sea view.

Henrietta’s diary entry for the date reads: “Went to Bourne. Slept there for the first time.”

This spring journey by carriage, which included a stop at Oakley for lunch, was to be the annual custom.

After a few years the couple preferred to stay at one of the other new houses such as the thatched Portman Lodge, intended for the butler. From 1820, The Mansion was let to the Marchioness of Exeter.

After the death of widowed Henrietta in 1846, the main house became Exeter House Collegiate School. Thirty years later the lease was purchased by Nicholas Newlyn, who opened it as Newlyn’s Family Hotel.

In 1881 his son Henry, who had managed gentlemen’s clubs in St James’s and catered for royalty, took charge. His wife Leonie was daughter of Charles Tessier, who had been Lord Salisbury’s chef at Hatfield House. This experience was useful in attracting important guests.

In Queen Victoria’s Golden Jubilee Year 1887 Henry changed the name to Newlyn’s Royal Exeter Park Hotel and added the crowns on the new tower.

This was just in time for the booking of his lifetime. Shortly after Easter weekend 1888 Empress Elizabeth of Austria arrived with a 28-strong entourage for a week’s stay. New curtains were hung and JJ Allen was engaged to carry luggage from the station.

To avoid language difficulties the gardener was dressed in a tabard with the German word for ‘water’ on one side and ‘milk’ on the other. When the Empress needed a sea water bath he was slapped on the back and when milk from the cow in the stables across the road was required he was poked in the chest.

Paths in the Winter Gardens grounds were candlelit in imitation of the custom at Vienna’s Schonbrunn Palace. Today’s Lower Pleasure Gardens illuminations custom are the legacy of the royal visit.

Another legacy is the right granted by the Empress for the hotel to fly her standard every Sunday. Newlyn again changed the hotel name to be the Royal and Imperial Exeter Park Hotel.

Henry Newlyn twice became mayor and on the second occasion, November 1895, the mayor-making ceremony was held at his hotel.

He retired before the First World War, which saw a final change of name to today’s Royal Exeter Hotel. By then Bournemouth had held its first centenary celebrations and the house had also reached its own centenary.

Other guests have included the Duke of Connaught, Queen Victoria’s third son who visited twice, and Oscar Wilde. In 2003 Tony Blair, as prime minister, was filmed at the hotel and in Bournemouth’s bicentenary year, 2010, former foreign secretary David Miliband chose the hotel for a reception during the Labour leadership hustings at the BIC opposite.

The Royal Exeter may have ceased to fly the Royal standard but it does raise the Cornish flag on Tregonwell’s birthday and have a restaurant called The 1812.

• Leigh Hatts is the author of Bournemouth’s Who Was Who (Natula, £11.95)