Georgius Hornius (Georg Horn, 1620–1670) was a German historian and geographer, and professor of history at Leiden University from 1653 until his death.
After a two year's sojourn in England, he returned to Leiden, compiling a history of the events of the ongoing English Civil War (Rerum Britannicarum libri VII, De statu ecclesiae Britannicae hodierno).
From about this time, he also began to suffer from intermittent spells of mental distraction, although he remained a prolific writer until his death.
His coverage of the Migration period is presented as the history of the "Scythian" nation, which is divided into Germans, Huns and Slavs.
In all his works, Horn presents himself as a pious Protestant and as a patriot of his homeland, considering himself a native of and exile from the Upper Palatinate (which had been annexed by the Catholic Duke of Bavaria in 1628).