Itt meaning

1899: William Clarke and Charles Harding Firth [ed.], The Clarke Papers: Selections from the Papers of William Clarke, Secretary to the Council of the Army, 1647–1649, and to General Monck and the Commanders of the Army in Scotland, 1651–1660, page 120 (Camden Society)

Itt hath indeed bin intended by the French army to lay siege to […] and in order thereunto a conquest hath bin made of the sconce Mardyk, which did nott indure siege above 2 dayes before itt yielded uppon discretion,1 but since the taking thereof the resolution of beseiging Dunkirk beginneth to slacken, and I suppose will bee quitte layd aside for this […]