▁the ▁F ert ile ▁C res cent , ▁a ▁Pers ian ▁region ▁so ▁named ▁for ▁its ▁place ▁between ▁the ▁Tig ris ▁and ▁Eu phr ates ▁rivers ▁that ▁offered ▁it ▁fert ile ▁land . ▁This ▁included ▁entire ▁trib al ▁chief dom s ▁such ▁as ▁the ▁Lak hm ids ▁in ▁a ▁less ▁controlled ▁area ▁of ▁the ▁S as an ian ▁Empire , ▁and ▁the ▁Gh ass an ids ▁in ▁a ▁similar ▁area ▁inside ▁of ▁By z antine ▁territory ; ▁these ▁political ▁units ▁of ▁Arab ▁origin ▁offered ▁a ▁surprising ▁stability ▁that ▁was ▁rare ▁in ▁the ▁region ▁and ▁offered ▁Arab ia ▁further ▁connections ▁to ▁the ▁outside ▁world . ▁The ▁L akh mid ▁capital , ▁H ira ▁was ▁a ▁center ▁for ▁Christian ity ▁and ▁Jewish ▁craft s men , ▁mer ch ants , ▁and ▁far mers ▁were ▁common ▁in ▁western ▁Arab ia ▁as ▁were ▁Christian ▁mon ks ▁in ▁central ▁Arab ia . ▁Thus ▁pre - I sl am ic ▁Arab ia ▁was ▁no ▁stranger ▁to ▁Abraham ic ▁relig ions ▁or ▁mon othe ism , ▁for ▁that ▁matter . ▁ ▁Islam ic ▁cal i ph ate ▁ ▁While ▁the ▁By z antine ▁Roman ▁and ▁S ass an id ▁Pers ian ▁emp ires ▁were ▁both ▁weak ened ▁by ▁war fare ▁( 6 0 2 – 6 2 8 ), ▁a ▁new ▁power ▁in ▁the ▁form ▁of ▁Islam ▁grew ▁in ▁the ▁Middle ▁East . ▁In ▁a ▁series ▁of ▁rapid ▁Muslim ▁con quest s , ▁Arab ▁arm ies , ▁led ▁by ▁the ▁C ali ph s ▁and ▁sk illed ▁military ▁command ers