Siemens first produced the Viaggio Comfort railcars in response to a request by the Austrian Federal Railways (ÖBB) for locomotive-hauled push-pull trainsets for its upcoming Railjet high-speed rail service.

[8] The trainsets were built at the Siemens factory in Maribor, Slovenia, and the first unit was completed on 15 September 2008, and put on display in several locations including the InnoTrans trade fair before beginning test runs in late 2008.

Between September 2011 and May 2012, České dráhy (ČD) negotiated to have seven of the trainsets ordered by ÖBB transferred to it, for use on its high-speed rail service which would also be called Railjet.

The units operate on domestic lines between Prague and Cheb via Plzeň or Ústí nad Labem.

The shape of the forward end of the control car will be derived from the design of the Siemens Vectron locomotives.

The trainsets were manufactured by Siemens in Maribor, Slovenia, with final assembly being completed by ÖBB's technical services department in Simmering, Vienna.

[16] Brake equipment is supplied by Knorr-Bremse, air-conditioning by Liebherr, and doors, carriage connections, toilets and seats are manufactured by other subcontractors.

Railcars are currently on order for the US states of California, Illinois, Michigan, and Missouri for use on their state-supported corridors operated by Amtrak.