Many of the written Constitutions of modern Europe came into being during the eighteenth and nineteenth centuries. The US Constitution, created in 1789, was influenced by the ancient Greek model. All the fifty states of the US have their own Constitutions. countries like India, Japan, Canada and Germany have their own written Constitutions.
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The unwritten Constitutions are those processes of government that are considered an essential part of the system, yet they are not actually in the Constitution. These are customs and precedents that have been in existence for so long that many citizens think these are, in fact, laws, yet not part of the Constitution.
England has no single written Constitution as such; it inheres in a body of legal customs and traditions that regulate the relationship between the monarchy, the legislature, the judicial system and the common law. Though the British Constitution is, in a sense, unwritten because it does not originate in a single document, many written laws have been instrumental in its creation.