A member of the order Cetacea, the blue whale (Balaenoptera musculus), is thought to be the largest animal ever to have lived. The maximum recorded weight was 190 metric tonnes for a specimen measuring 27.6 metres (91 ft), whereas longer ones, up to 33.6 metres (110 ft), have been recorded but not weighed.
<span>The major accomplishments of Charlemagne include developing the rules of the feudal system, encouraging reading and writing throughout his empire, developing commerce with a unified monetary system, and the unification of all Germanic peoples into a single kingdom through his crusades, which sought to convert all subjects to Christianity.</span>
