Proto-West Germanic *swarjan

→ English swear (inherited)

→ Old English swerian (inherited)

→ German schwören (inherited)

→ Middle Dutch sweren (inherited)

→ Middle English sweren (inherited)

→ Middle High German swern (inherited)

→ Old High German sweren (inherited)

→ Dutch zweren (inherited)

→ Old Dutch sweren (inherited)

→ Old Frisian swera (inherited)

→ Old Saxon swerian (inherited)