The Oxfordshire Ironstone Company, of Banbury, at one time owned a fleet of twenty steam locomotives which were employed in handling iron ore trains from the workings at Wroxton to the exchange sidings of the Great Western Company at Pen Hill, near Banbury, a distance of about five miles.  These engines were maintained in first class condition but eventually the introduction of diesels made them redundant.

The survivor was supplied to the Oxfordshire Ironstone Company in 1918 by Hudswell Clarke & Co of Leeds, as one of  two six-coupled tank engines. They were given fleet numbers 1 and 2 and named Sir Thomas and Lord North respectively. A similar engine, President, was delivered in 1923.  Sir Thomas was named after Sir Thomas Pope, the first owner of Wroxton Abbey, which was close to the company's workings.  Sir Thomas was relatively unusual for an industrial locomotive in that it was fitted with vacuum brake equipment from new.

In the mid-1960s, the steam locomotives were replaced by diesels, and at the instigation of Mr E. Tonks of the Birmingham Locomotive Club, Sir Thomas was saved for preservation, and presented to the Quainton Railway Society on 1st June 1969. Sir Thomas headed the Quainton Railway Centre's first passenger trains along with Juno, in August 1969.  Sir Thomas and Juno then bore the brunt of services for the next two years.  In 1971 very major work became necessary and it is now a long-term static exhibit.