Completed in 1857 the ship participated in the Second Italian War of Independence in 1859 and the initial stages of the Second French intervention in Mexico before she was converted into a troopship in 1862 or 1863.

The conversion to steam power involved cutting the ship's frame in half amidships and building a new section to house the propulsion machinery and coal bunkers, which reduced her armament to 90 guns.

Details are lacking on Eylau's propulsion machinery, the only information available is that her two steam engines were rated at 900 nominal horsepower[1] and produced 3,600 metric horsepower (2,600 kW).

On the quarterdeck and forecastle were twenty 30-pounder cannon and a pair of 163 mm (6.4 in) rifled muzzle-loading guns.

[3] The ship was ordered in the early 1830s under the name Éole and was laid down at the Arsenal de Toulon in August 1833.