The Trust was established in 1936 by John Scott, owner of the Manchester Guardian (as it then was) and the Manchester Evening News. After the deaths of his father C. P. Scott and brother Edward, John Scott wished to prevent death duties forcing the closure or sale of the newspapers, and to protect the liberal editorial line of the Guardian from interference by future proprietors.
The Trust was reformed in 1948, as it was thought the terms of the original Trust Deed might still be liable to tax. At this time John Scott also gave up his exclusive right to appoint trustees; the trustees now appoint new members themselves. It is normal practice for a Guardian journalist to be a member of the trust, though they are not considered to be a "representative" of the staff as this may result in a conflict of interests.
The Trust is responsible for appointing the editor of The Guardian (and those of the group's other main newspapers) but apart from enjoining them to continue the paper's editorial policy on "the same lines and in the same spirit as heretofore", has a policy of not interfering in their decisions. This arrangement tends to give editors a long tenure, and it is probably for this reason that internal appointments have been preferred. GMG's acquisition of The Observer, however, was followed by a quick succession of editors, amid reports of intrigue and accusations of interference.
In 1992 the Trust identified its central objective as being:
The current chair of the Trust is Liz Forgan, a former Director of Programmes at Channel 4 and Managing Director of BBC Radio. She was appointed in November 2003 to fill the vacancy left by the death of Hugo Young. Other trustees include the current Guardian editor Alan Rusbridger, the former editor Peter Preston, and two members of the Scott family.
Forgan is the sixth chair of the trust; her predecessors were John Scott (1936-48), A. P. Wadsworth (1948-56), Richard Scott (1956-84), Alistair Hetherington (1984-89) and Hugo Young (1990-2003).