ht . ▁▁ ▁The ▁concept ▁of ▁the ▁" Middle ▁Kingdom " ▁as ▁one ▁of ▁three ▁" g old en ▁ages " ▁was ▁co ined ▁in ▁ 1 8 4 5 ▁by ▁German ▁Egypt ologist ▁Baron ▁von ▁Bun sen , ▁and ▁its ▁definition ▁evol ved ▁significantly ▁throughout ▁the ▁ 1 9 th ▁and ▁ 2 0 th ▁centuries . ▁Some ▁sch ol ars ▁also ▁include ▁the ▁Th ir teenth ▁D ynast y ▁of ▁Egypt ▁wh olly ▁into ▁this ▁period , ▁in ▁which ▁case ▁the ▁Middle ▁Kingdom ▁would ▁end ▁around ▁ 1 6 5 0 ▁BC , ▁while ▁others ▁only ▁include ▁it ▁until ▁Mer ne fer re ▁Ay ▁around ▁ 1 7 0 0 ▁BC , ▁last ▁king ▁of ▁this ▁dynast y ▁to ▁be ▁att ested ▁in ▁both ▁Upper ▁and ▁Lower ▁Egypt . ▁During ▁the ▁Middle ▁Kingdom ▁period , ▁Os ir is ▁became ▁the ▁most ▁important ▁de ity ▁in ▁popular ▁religion . ▁The ▁Middle ▁Kingdom ▁was ▁followed ▁by ▁the ▁Second ▁Inter mediate ▁Period ▁of ▁Egypt , ▁another ▁period ▁of ▁division ▁that ▁involved ▁foreign ▁invas ions ▁of ▁the ▁country ▁by ▁the ▁Hy ks os ▁of ▁West ▁Asia . ▁ ▁Political ▁history ▁ ▁Re un ification ▁under ▁the ▁Ele vent h ▁D ynast y ▁ ▁After ▁the ▁collapse ▁of ▁the ▁Old ▁Kingdom , ▁Egypt ▁entered ▁a ▁period ▁of ▁weak ▁ph ara onic ▁power ▁and ▁decent ral ization ▁called ▁the ▁First ▁Inter mediate ▁Period . ▁Tow ards ▁the ▁end ▁of ▁this ▁period , ▁two ▁rival ▁dynast ies , ▁known ▁in ▁Egypt ology ▁as ▁the ▁T enth ▁and ▁Ele