The appointment follows a competitive pitch process, replacing previous incumbent Haggie Financial.
Chaucer Holdings was in the news recently after its CEO Bob Stuchbery indicated that it was considering relocating overseas to reduce its tax bill. The firm is currently one of only three Lloyd's of London insurers based in the UK.
The Citigate team is led by directors Justin Griffiths, Sarah Gestetner and Grant Ringshaw.
CDR's financial services team already houses retained insurance clients such as Aspen Re, LV=, Partner Re and Prudential.
Stuchbery said of the appointment: ‘We are delighted to appoint Citigate Dewe Rogerson to support our new senior management team and we look forward to working with them.'