Jacobstow (Cornish: Lannjago) is a civil parish and village in north Cornwall, England, United Kingdom.

[2] Penhallym in the north of the parish is mentioned (as Penhalun) in the Domesday Book;[3] nearby is Penhallam, site of a medieval manor.

The name Jacobstow originates from Saxon times and derives from St James (Latin Jacobus) and holy place.

[3] As well as the church town, other settlements in the parish include Southcott and those parts of Canworthy Water north of the River Ottery.

[5][6] Degory Wheare, a historian, the first Camden Professor of Ancient History in the University of Oxford, was born in Jacobstow.