Julian was first elected the MP on 6 May 2010, with a majority of 9,950 votes.

After being re-elected in 2015, Julian joined the Government in the Whips Office, serving as Vice Chamberlain of HM Household from July 2016-June 2017.

In June 2017, Julian was re-elected as the Member of Parliament for Skipton and Ripon with a majority of 19,985.

Julian was then promoted to Deputy Chief Whip, a position he held until being appointed Government Chief Whip in November 2017. Julian served in this role for just under 2 years.

Julian is currently the Secretary of State for Northern Ireland, being appointed to the role in July 2019 by the new Prime Minister, Boris Johnson.