Identification terms

Identification terms (long answer) the following terms:

1- Abbasids.

2- Charlemagne.

3- Constantine.

4- Constitution of Medina.

5- Dar al-Islam.

6- Gregory the Great.

7- Justinian I.

8- Third Century Crisis.

 

Each term should be the answer of these questions and an small essay. The questions are Who, What, When, Where, What happened, Why important.

Each Identification should be around 6 and 7 sentences.

Be sure, to write easy words and easy vocabularies. Because I am international student and my English writing is very weak. Also I want to be free plagiarism.