143rd field regiment mobilized on 3 september 1939 at ashford under eastern command with 386th (duke of connaught's own yeomanry) and 388th (queen's own yeomanry) batteries. it spent the early part of the war in iceland. while there, it was reorganised from two 12-gun batteries to three 8-gun batteries when the third battery (507th) was formed in the regiment in may 1941. it was authorised to use the "kent yeomanry" designation from 17 february 1942.