What nation came to rival britain's economic output right before world war 1

The answer is Germany. Starting in the late 19th century forwards Britain had a relative economic decline as other states such as the United States and Germany held up. In 1870, Britain's output per head was the second highest in the world after Australia. By 1914, it was fourth in the ranking. This was before the World War 1. 

Answer

Germany

Explanation

Some years before the world war 1, Britain and Germany  had trade rivalry. Their rivalry was as a result of both countries had developed their markets in the different parts of the world. Britain had developed their markets within the their own Empire while Germany on the Europe. But the economic rivalry did not play a major role in the cause of the first world war.

In economics, a good are  said to be rivalrous or rival if their consumption by one consumer prevents simultaneous consumption by other consumers, or if consumption by one party reduces utility/ability to use to another. Thus if two countries are offering goods and services in their markets that is mostly in the international markets where there is high market competition because each country wants its economy to grow. Thats what happened between Germany and Britain Before world war 1.

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