英语语法问题,这个that有没有必要留着?

英语语法问题,这个that有没有必要留着?
明朝第三位皇帝朱棣在夺取(usurp)帝位后,从南京迁都北京,于1406年开始建造紫禁城这座宫殿,至明永乐十八年（1420年）落成.
After that Zhu Di,who was the third emperor of Ming Dynasty,usurped the throne,hemoved the capital from Nanjing to Beijing and he began to construct the ForbiddenCity from 1406 to Ming Yong Le eighteenth years(1420).