At the time the British ruled about 25% of the Earth's surface and this caused Germany to be jealous of the amount of power Britain had. .
Italy and Germany wanted a colonial empire too and also wanted to expand but they could not as they were surrounded on every side by powerful countries. The fact that the British had so many colonies around the world forced Germany to demand more and increased their rivalry, this contributed partially to WW1. This wasn't the only rivalry Britain and Germany had; they also had Economic Rivalry, a long-term factor for that contributing to the break out of the Great War. There were economic conflicts between Germany and Britains from 1890 onwards. The British had introduced an effective battle ship called the 'Dreadnought' in 1906 and Germany soon followed suit introducing their own battleships. Germany and the USA's economic strength was rising in their exports of steel and coal while Britain's economic strength was falling due to this. There were also economic struggles between France and Germany. In 1870, France had already lost two of her coal producing provinces to Germany and from 1871 onwards France had to import coal from other countries. This meant France had to compete with Germany in Morocco because the place was rich in mineral resources. The last long term factor is revenge. France wanted revenge on Germany from the Franco-Prussian War in the years 1870 and 1871. During this war Germany had claimed French land, Alsace-Lorraine as their own and France were not happy at all about this and wanted revenge.
The first short-term factor I would like to put across was the war plans which I also think was the least important factor. All major European countries had drawn up war plans. Count Alfred Von Schlieffen, a German General drew up a plan of action which he called the 'Schlieffen Plan'. This involved attacking France through Belgium and encircle Paris, all within 6 weeks.