During the First World War, large scale requisitioning of big country houses occurred for military headquarters or hospitals. Burghley House became a convalescent house for troops. For the servants remaining, additional work was often created by the arrival of evacuees or patients.

Each band of soldiers usually stayed six weeks then they were sent back to France — to the muddy trenches, the fighting, and the gas attacks, some never to come back again. It was sad to see each lot go, but it had been nice for them to convalesce at Burghley.
Bertha Adams Johnstone.

The pleasure parks were also commandeered and suffered damage as vegetable plots, practice grounds or merely from neglect.

In the Second World War, a bomb landed in the grounds at Burghley and the shrapnel damage can still be seen in the trees. It is rumoured that the pilot was executed because Göring wanted the house and the collection for himself when they invaded England.

One night we were turned out as a German Zeppelin was sighted; it came over us as we were walking home in the park. There was a new R.A.F. station at Wittering which is still there today. The Royal Air Force had just been formed and some of the American airmen were stationed there. The Zeppelin dropped a bomb near there but luckily it did no damage.
Bertha Adams Johnstone.

On the death of the Sixth Marquess, the direct ownership of the house passed to a family trust, which still owns and manages Burghley House. The house contains thirty-five major rooms and eighty lesser rooms, halls, corridors, bathrooms and service areas, of which eighteen rooms are open to the public. Entrance to the park is free, and many public events have been held there in recent years.

Twelve acres of scrub woodland have been reclaimed for the Sculpture Gardens, which contain contemporary sculpture and hold annual displays of new work. The ten thousand-acre estate funds the upkeep of the house through agriculture and property rents.

A major annual occasion at Burghley is the ‘Burghley Horse Trials’, which was devised by the Sixth Marquess. It is a three-day event held by the British Horse Society since 1961. The first World Championship was staged at Burghley in 1966, and a subsequent event in 1974. They have also hosted five European Championships, and the Young Riders European Championship in 1978.