This is the second lesson of two on the Byzantine Empire. Throughout the course of world history, borders have changed as various groups of people competed to control and rule territory and acquire resources. Throughout time, empires have expanded and collapsed. The Byzantine Empire once occupied the eastern portion of the Roman Empire with Constantinople as its capital, but yet disappeared from the map in 1453 when Constantinople became the capital of Ottoman Empire. Through an investigation of a series of map layers and examination of an interactive Web site, students discover how and why the borders of the Byzantine Empire changed through time. Key questions: What factors influence border changes? What are the effects of changing borders?

The first of two lessons on territorial extent of empires in Europe in 814 at the end of Charlemagne’s rule and another after the death of Charlemagne. Students extend and refine their map interpretation skills by examining the use of color to denote territorial ownership. In addition, students make predictions about likely paths of invasion. Key questions: How do physical geography, cultural, economic, and political factors affect borders? To what extent does the physical environment define borders?

First of three lessons examine changing European borders, students compare maps illustrating changes of Europe's division of territory from 1000 A.D. (C.E.) to 1450 A.D. (C.E.). Unification of smaller regions into a larger state may form the basis for political power and the ability to exert influence over other countries. Students uncover the relationship between territorial extent and political power. Key questions: How did the consolidation of territory affect the formation of nation states?; How could stable borders contribute to the political stability of a state?

The second of two lessons on Islamic Empires, students examine maps showing the territorial extent of each of the three major Islamic Caliphates. This examination, showing the same territory through different time periods, provides a springboard for analyzing historical factors underlying the territorial changes. Students also explore cultural, economic, and political factors that account for the changing borders as they match explanations associated with the changes in the maps. Key questions: How did the borders of the Islamic Empires change through time? What cultural, economic, and political factors could account for the changing borders?

This lesson is a Jamboard on perimeter of triangles. Students will use the Desmos calculator to compute the problems. Also, students will use the formula sheet.