$  Engineering forces undergone rapid development during the Great War.  Positional warfare required well    $
$developed fortified lines, minefields, etc.  Polish Army, created after the Great War was influenced by the $
$French doctrine, stating the advantage of positional defence over the mobile warfare.  As a result,         $
$engineering forces were overly expanded.  In thirties, when French influence eroded, engineering forces     $
$were neglected.  In 1939 many Polish engineering units were supplied with obsolete materiel.  Every         $
$infantry division had its own engineering battalion.  Its task in advance comprised clearing minefields     $
$and obstacles.  When on defence, sappers were prepared to blow up bridges, built defensive lines and        $
$minefields.                                                                                                 $
