Deuteronomy 3:8

8 We took the land of the two Amorite kings east of the Jordan River, from the Arnon Valley to Mount Hermon.

Deuteronomy 3:8 Meaning and Commentary

Deuteronomy 3:8

And we took at that time out of the hands of the two kings of
the Amorites
Sihon king of Heshbon, and Og king of Bashan;

the land that [was] on this side Jordan;
where Moses then was, being in the plains of Moab, and was the country beyond Jordan, with respect to the land of Canaan, and when in that:

from the river of Arnon unto Mount Hermon;
Arnon was a river which divided Moab and the Amorites, ( Numbers 22:13 ) and Hermon was a mountain of Gilead, which ended where Lebanon began, and was the northerly border of this country. It was remarkable for the dew that fell on it; (See Gill on Psalms 133:3).

Deuteronomy 3:8 In-Context

6 We claimed them all for God, destroying every city, including men, women, and children--as we did to King Sihon of Heshbon.

7 However, we did loot the cities, taking all of the cattle and goods.

8 We took the land of the two Amorite kings east of the Jordan River, from the Arnon Valley to Mount Hermon.

9 (The Sidonians call Mount Hermon by the name Sirion, and the Amorites call it Senir.)

10 We took all of the cities of the plateau, all of Gilead, and all of Bashan as far as Salcah and Edrei, cities of Og's kingdom in Bashan.