Longford is in east central Ireland.

Part of the Irish central plain, Longford is bounded on the west by the River Shannon and on the southwest by Lough Ree. The land is generally flat, with many bogs and lakes.

The area is well suited for cattle raising, which is the economic mainstay. The major farm crops are potatoes and oats.

It was known as Annaly when owned by the O'Farrell family prior to the 12th century. Longford was established as a shire in 1569.