This spread of Islamic culture was facilitated by trade, missionaries, and changes in the political structure of Islamic society. As a result, we encounter multiple different interpretations of Islam across many different Islamic societies.

From 9th century to the 12th century, Islamic culture flourished and crystallized into what we now recognize as Islam. The military expansions of the earlier period spread Islam in name only; it was later that Islamic culture truly spread, with people converting to Islam in large numbers.

This spread of Islamic culture was facilitated by trade, missionaries, and changes in the political structure of Islamic society. As a result, we encounter multiple different interpretations of Islam across many different Islamic societies

Explanation:

Islam was once concentrated only around the Abbasids massive empire which spans across four thousand miles but was very difficult to maintain. As people converted to Islam, tax revenue collected from non-muslim dwindled, and the Abbasid's court expenditure could no longer be sustained. This led to to Abbasid caliphate fragments into smaller, independent political structure then diminished the Abbasid's power.

These political distabilization and decentralization of the Abbasids led to the spread of Islam beyond Abbassids empire borders.

After the fall of the Abbasids, Islamic structures transformed beyond traditional Arab Muslim elites, there were conversion between other religion such as Christian and Judaism, also alternative Social and political structures filled the vaccum of the Abbasids political structure and one of those alternative structures is the Sufi religious institutions, the Sufi missionaries were responsible for many conversions in sub-saharan Africa, in South and Southeast Asia. This assimilations with different cultures and people resulted in the mix of islamic traditions with pre-Islamic beliefs thereby allowing for different interpretation of Islam.

Also, Islam travelled through trade, caravans, which is a group of travelers that used camels to transport themselves and goods were critical to the spread of Islam. Advanced road networks enabled the caravans filled with soldiers, Pilgrims, envoys, merchants, and scholars to travel vast territories and along the trade routes, merchant communities developed into Muslim controlled parts and they equally brought their own interpretation to the traditional Islam am they have converted to.