Mr Engelhardt set up Admiral in 1993
The American businessman who founded an insurance firm which employs more than 2,500 people in Cardiff and Swansea has been presented with an honorary CBE.
Henry Engelhardt, chief executive of Admiral, has been honoured for his services to the insurance industry in Wales.
The company owns several insurance brands including Elephant and price comparison website Confused.com.
Admiral unveiled a 24% jump in profits topping £182.1m during 2007.
Welsh Secretary Paul Murphy presented the award to Engelhardt, 50, on behalf of the Queen at a ceremony in Cardiff.
"The history of Admiral is one of amazing growth and innovation in Wales," Mr Murphy said.
"Mr Engelhardt set up the company in 1991 and since then his many achievements have included the development of Admiral's business in the UK, leadership of its strategic and policy direction and winning new business.
"Admiral is one of Wales' biggest success stories and has added greatly to the employment opportunities in Cardiff, Swansea and the surrounding areas."
The company has launched operations in Spain and Germany.
In September 2004 Admiral's employees received an average windfall of about £37,000 as the company sold a 10% stake.
In December 2007 Admiral Insurance broke into the FTSE 100 Index of top British companies.