Captain William Henry Irvine Shakespear, CIE (29 October 1878 – 24 January 1915), was a British civil servant and explorer who mapped uncharted areas of Northern Arabia and made the first official British contact with Ibn Sa'ud, future king of Saudi Arabia.

While in Kuwait, Shakespear made seven separate expeditions into the Arabian interior, during which he became a close friend of Ibn Sa'ud, then the Emir of the Nejd.

In March 1914, Shakespear began a 2,900-kilometre (1,800 mi) journey from Kuwait to Riyadh and on to Aqaba via the Nafud Desert, which he mapped and studied in great detail, the first European to do so.

In November 1914, the British government in India asked Shakespear to secure Ibn Sa'ud's support for the British-Indian Mesopotamian Expeditionary Force, which had just taken Basra.

Had he survived to continue a work for which he was so eminently suited, it is extremely doubtful whether subsequent campaigns of Lawrence would ever have taken place in the west..."