original_query: What was the purpose of the 191st (Hertfordshire and Essex Yeomanry) Field Regiment during World War II?
query: What was the purpose of the 191st (Hertfordshire and Essex Yeomanry) Field Regiment during World War II?
answer: The 191st (H&EY) Field Regiment served as mobile artillery, supporting various formations like Royal Marine Commandos and Polish troops under the First Canadian Army in Northwest Europe.