The Methuen Convention was an offensive military and commercial treaty signed between Portugal and England in 1703 as part of the Spanish Succession War.
The Treaty stipulated that no tax could be levied on Portuguese wines exported to England or to English textiles exported to Portugal regardless of the geopolitical situation of each of the two nations (this was to ensure that England still Portuguese wine would accept at times when it was not in war with France).
Some authors argue that the agreement was negative for Portugal, as it meant that the country would not develop its industrial infrastructures and other types of agricultural products (and thus lost the industrial race). However, this is debatable because this period saw the rise of other industries in Portugal, such as porcelain production. Some of the factories that appeared during that period still exist.
By virtue of this treaty, Portugal maintained a strong political position at a stage in which it realized that it was fundamental that it would retain the territorial integrity of its main colony, Brazil (as expressed by Brazilian economist Celso Furtado in his work the "Brazilian Economic Foundation".
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