Romans came from the Italian pensinsula and came to Britain in the early first century. It was a gradual process and they slowly started conquering the different parts of the British isles during that time. 
Vikings came from the Northern parts of Europe and they started conquering the British isles in later periods. 
Both came and wanted to conquer the lands, while Romans were 'established' conquerors and started governing these areas soon by spreading their culture etc. The Vikings on the other hand had pillaing more in mind and did more of that and did not govern that much from the beginning. 
        
             
        
        
        
Because of the super rich in protean soil. ~Matya
 
        
             
        
        
        
The government of ancient Athens was "a direct democracy," since in fact the Ancient Greeks were the ones who "invented" democracy in the first place. 
        
                    
             
        
        
        
<span>Guglielmo Marconi's work was in radio signals, and one of his inventions was the radio telegraph (AKA wireless telegraph)</span>
        
             
        
        
        
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The disease progressed to a chronic illness in up to 25% of patients, and its late neurologic manifestations had a profound affect on Western history when it infected societal leaders; on societal morays as a means to curb the disease; and on public health practices. When the Medical Research Council conducted its survey of medical advances of greatest import, the largest number of responses was for the discovery of antibiotics by Alexander Fleming.
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