 The changes in warfare during the Early Middle Ages to heavy cavalry both precipitated and relied on the arrival of the stirrup, solid-treed saddle, and horseshoe from other cultures.The development of the nailed horseshoe enabled longer, faster journeys on horseback, particularly in the wetter lands in northern Europe, and were useful for campaigns on varied terrains.By providing protection and support, nailed horse shoes also improved the efficiency of draught horse teams.