▁on ▁Th urs day ▁( link ▁will ▁display ▁the ▁full ▁calendar ) ▁of ▁the ▁Julian ▁calendar . ▁The ▁den om ination ▁ 7 8 4 ▁for ▁this ▁year ▁has ▁been ▁used ▁since ▁the ▁early ▁medieval ▁period , ▁when ▁the ▁An no ▁Dom ini ▁calendar ▁era ▁became ▁the ▁pre val ent ▁method ▁in ▁Europe ▁for ▁naming ▁years . ▁ ▁Events ▁▁ ▁By ▁place ▁▁ ▁Europe ▁▁ ▁Sax on ▁Wars : ▁King ▁Char lemagne ▁begins ▁a ▁campaign ▁in ▁northern ▁Sax ony . ▁He ▁rav ages ▁East phal ian ▁territory ▁as ▁far ▁as ▁the ▁El be ▁River , ▁while ▁his ▁son , ▁Charles ▁the ▁Young er , ▁defe ats ▁a ▁Sax on ▁force ▁in ▁the ▁Li ppe ▁Valley . ▁Bad ▁weather ▁h ind ers ▁Char lemagne ' s ▁winter ▁campaign ▁in ▁southern ▁Sax ony . ▁▁▁ ▁Winter ▁– ▁Char lemagne ▁returns ▁to ▁E res burg ▁and ▁builds ▁a ▁church , ▁probably ▁on ▁the ▁site ▁of ▁the ▁I rm ins ul ▁( a ▁pag an ▁religious ▁site ). ▁Frank ish ▁forces ▁based ▁at ▁E res burg ▁attack ▁re bel ▁Sax on ▁settlement s , ▁and ▁take ▁control ▁of ▁the ▁roads . ▁Char lemagne ▁himself ▁takes ▁part ▁in ▁some ▁of ▁these ▁ra ids . ▁▁ ▁Arab ian ▁Empire ▁▁ ▁Abd ▁al - R ah man ▁I , ▁Muslim ▁em ir ▁of ▁C ór dob a ▁( Al - And alus ), ▁begins ▁the ▁construction ▁of ▁the ▁P ray er ▁Hall ▁of ▁the ▁Great ▁Mos que ▁of ▁C ór dob a . ▁He ▁uses ▁the ▁mos que ▁( origin