JuliánCastro完成学业后，他和他的兄弟在Akin Gump Strauss Hauer＆Feld律师事务所工作，后来离开了自己的公司。两兄弟也追求政治生涯，使罗西卡斯特罗对他们的影响显而易见。朱莉安·卡斯特罗于2001年赢得了圣安东尼奥市议会的选举，当时他才26岁，使他成为有史以来最年轻的市政委员。后来，他把目光投向了市长竞选活动，但最初的竞标失败了。 JoaquínCastro于2003年在德克萨斯州众议院获得一席之地。2007年，Julián与小学老师Erica Lira结婚。这对夫妇在2009年有了他们的第一个孩子，一个名叫Carina的女儿。同年，卡斯特罗最终当选圣安东尼奥市长，直到2014年，他的儿子CristiánJuliánCastro出生的那一年。在担任市长期间，卡斯特罗在北卡罗来纳州夏洛特举行的2012年民主党全国代表大会上发表了鼓舞人心的主题演讲，这使他与八年前参加大会的美国参议员巴拉克•奥巴马（Barack Obama）的演讲相提并论。在他的主题演讲中，卡斯特罗讨论了美国梦和他的家人为帮助他实现这一目标而做出的牺牲。
After Julián Castro completed his studies, he and his brother worked at Akin Gump Strauss Hauer & Feld and later left their company. The two brothers also pursued a political career, making Rossi Castro’s influence on them obvious. Julian Castro won the San Antonio City Council election in 2001, when he was 26 years old, making him the youngest municipal council member ever. Later, he turned his attention to the mayoral campaign, but the initial bid failed. Joaquín Castro gained a place in the Texas House of Representatives in 2003. In 2007, Julián married elementary school teacher Erica Lira. The couple had their first child in 2009, a daughter named Carina. In the same year, Castro was elected to the mayor of San Antonio until 2014, when his son Cristián Julián Castro was born. During his tenure as mayor, Castro delivered an inspiring keynote speech at the 2012 Democratic National Convention in Charlotte, North Carolina, which brought him to the US Senator Barak, who attended the conference eight years ago. Barack Obama’s speech is comparable. In his keynote speech, Castro discussed the American dream and his family’s sacrifices to help him achieve this goal.