<Li> June 23--The Hungarians besiege Lérida for 8 days, then attack Cerdaña and Huesca . </Li> <Li> June 26--The Hungarians capture Yahya ibn Muhammad ibn al Tawil, the ruler of Barbastro, and hold him captive 33 days, until he is ransomed . </Li> <Li> July--The Hungarians find themselves on desert territory andrun out of food and water . They kill their Italian guide and return home . Five Hungarian soldiers are taken prisoner by the Cordobans and become bodyguards of the caliph . </Li> <Li> 943 <Ul> <Li> Balkans <Ul> <Li> Allied with the Russians, a Hungarian army attacks the Byzantine Empire . Emperor Romanos I Lekapenos buys peace, and accepts to pay a yearly tribute to the Hungarians . </Li> </Ul> </Li> <Li> Bavaria <Ul> <Li> The Hungarians who attacked Bavaria, are defeated in the Battle of Wels by Berthold, Duke of Bavaria and the Carantanians . </Li> </Ul> </Li> </Ul> </Li>

Who are the invaders attacking western europe and why are they invading