刘焉(yān )是汉鲁恭(gōng )王之后裔,以汉朝宗室身份,拜(bài )为中郎(láng ),历(lì )任(rèn )雒(luò )阳令,冀州(zhōu )刺史,南(nán )阳(yáng )太守,宗正,太(tài )常等官。后因益州刺史郄俭(jiǎn )在(zài )益州(zhōu )大事聚敛,贪(tān )婪成风(fēng ),加(jiā )上当时天下大(dà )乱,刘焉欲取得一安身立命之所,割据(jù )一方。于是刘焉向朝廷求为益(yì )州牧,封阳城(chéng )侯,前往益州(zhōu )整饬吏治。后郗俭为(wéi )黄巾(jīn )贼所杀,刘焉(yān )进(jìn )入(rù )益州,派张鲁(lǔ )盘踞汉中(zhōng ),