The 100 ft tree was planted in 1856 and each winter would be dug up and taken into the mansion at West Park in Silsoe with its roots still attached.
When it grew too big for the house it was planted for good in the grounds where it stood undecorated for decades.
But this year a 3 ft star will be put on the top and visitors to the English Heritage estate will be invited to decorate the lower branches with ribbons.
A spokesperson said reference to its use as a Christmas tree was recently found in an edition of Gardener’s Chronicle dated June 1900.
The article stated the tree was planted in 1856 and “must therefore have been one of the first introduced into this country”.
John Watkins of English Heritage said: “Christmas trees were the height of festive fashion by the 1850s after being adopted by the Royal family as part of their celebrations. This was planted shortly after the trend began and we believe it is one of the earliest examples.”