 With the outbreak of the Hundred Years ' War in 1337 , Grosmont 's attention was turned towards France . He took part in several diplomatic missions and minor campaigns and was present at the great English victory in the naval Battle of Sluys in 1340 . Later the same year , he was required to commit himself as hostage in the Low Countries for the king 's considerable debts . He remained hostage until the next year and had to pay a large ransom for his own release . On his return he was made the king 's lieutenant in the north and stayed at Roxburgh until 1342 . The next years he spent in diplomatic negotiations in the Low Countries , Castile and Avignon . 
 With the outbreak of the Hundred Years <a href='null_genetive' title='1'><mark>'</mark></a>War in 1337 , Grosmont <a href='null_genetive' title='2'><mark>'s</mark></a>attention was turned towards France . He took part in several diplomatic missions and minor campaigns and was present at the great English victory in the naval Battle of Sluys in 1340 . Later the same year , he was required to commit himself as hostage in the Low Countries for the king <a href='null_genetive' title='3'><mark>'s</mark></a>considerable debts . He remained hostage until the next year and had to pay a large ransom for his own release . On his return he was made the king <a href='null_genetive' title='4'><mark>'s</mark></a>lieutenant in the north and stayed at Roxburgh until 1342 . The next years he spent in diplomatic negotiations in the Low Countries , Castile and Avignon . 
With the outbreak of the Hundred Years  War in 1337 , Grosmont  attention was turned towards France . He took part in several diplomatic missions and minor campaigns and was present at the great English victory in the naval Battle of Sluys in 1340 . Later the same year , he was required to commit himself as hostage in da Low Countries for the king  considerable debts . He remained hostage untill the next year and had to pay a large ransom for his own release . On his return he was made the king  lieutenant in the north and stayed at Roxburghtilll 1342 . Tdanext years he spent in diplomatic negotiations in thdaow Countries , Castile and Avignon .