ir teenth ▁century ) ▁were ▁built ▁by ▁them . ▁In ▁ 1 4 2 9 , ▁Joan ▁of ▁Arc ▁made ▁Blo is ▁her ▁base ▁of ▁operations ▁for ▁the ▁relief ▁of ▁Or lé ans . ▁Joan ▁of ▁Arc ▁rode ▁the ▁thirty - five ▁miles ▁on ▁Wed nes day ▁ 2 9 ▁April ▁to ▁Blo is ▁to ▁rel ieve ▁Or lé ans . ▁After ▁his ▁capt ivity ▁in ▁England , ▁Charles ▁of ▁Or lé ans ▁in ▁ 1 4 4 0 ▁took ▁up ▁his ▁residence ▁in ▁the ▁château , ▁where ▁in ▁ 1 4 6 2 ▁his ▁son , ▁afterwards ▁Louis ▁XII , ▁was ▁born . ▁In ▁the ▁ 1 6 th ▁century ▁Blo is ▁was ▁often ▁the ▁resort ▁of ▁the ▁French ▁court . ▁The ▁Tre aty ▁of ▁Blo is , ▁which ▁tempor arily ▁halt ed ▁the ▁Italian ▁Wars , ▁was ▁signed ▁there ▁in ▁ 1 5 0 4 – 1 5 0 5 . ▁ ▁The ▁city ' s ▁inhabitants ▁included ▁many ▁Cal vin ists , ▁and ▁in ▁ 1 5 6 2 ▁and ▁ 1 5 6 7 ▁it ▁was ▁the ▁scene ▁of ▁strugg les ▁between ▁them ▁and ▁the ▁supp or ters ▁of ▁the ▁Catholic ▁Church . ▁In ▁ 1 5 7 6 ▁and ▁ 1 5 8 8 ▁Henri ▁III , ▁king ▁of ▁France , ▁chose ▁Blo is ▁as ▁the ▁meeting - place ▁of ▁the ▁States - General , ▁and ▁in ▁ 1 5 8 8 ▁he ▁brought ▁about ▁the ▁mur ders ▁of ▁Henry , ▁du ke ▁of ▁Gu ise , ▁and