He was the son of a German immigrant – Frederick Jacobus Wepener – and a Cape Colony woman – Johanna Maria Erasmus.

Wepener was first married to Hester Susanna Nel and then later to Hilletje Maria Levina Van Aardt.

He later migrated to the Orange Free State where he bought two farms in Bethulie district – Constantia and Moordernaarspoort.

The wars resulted in the Orange Free State acquiring large tracts of land from Basotho.

The Free State's forces were led by Commandant-General Johan Fick and Commandant Louw Wepener.