why did the industrialized nations of the world embark so aggressively upon imperialist ventures between 1880 and 1914?

Greed!

They wanted cheap raw materials and they wanted to sell their manufactured products to captive customers.

The period between 1880 and 1914 saw a significant expansion of European imperialist ventures. There are several factors that contributed to this aggressive pursuit of imperialism by the industrialized nations:

1. Economic Motives: Industrialized nations sought to secure new markets and sources of raw materials for their industries. With the Industrial Revolution in full swing, there was a surge in production, and these nations needed new outlets to sell their goods and ensure a continuous supply of resources.

2. Nationalism and Competition: The pursuit of empire was often driven by nationalistic fervor and the desire to assert dominance over other nations. This resulted in intense competition between European powers to acquire colonies, expand influence, and demonstrate their supremacy on the global stage.

3. Strategic and Military Considerations: Control over territories provided military advantages such as naval bases, coaling stations, and trade routes. Dominance in these areas enabled countries to project their power and ensure national security.

4. Social Darwinism and Racial Superiority: During this period, ideas grounded in Social Darwinism and racial superiority gained popularity. Europeans believed that they were racially and culturally superior and, therefore, felt justified in dominating and "civilizing" other less-developed societies.

5. Technological and Scientific Advancements: Industrialized nations had superior military technology, such as advanced firearms, steamships, and telegraph systems. These advancements gave them an upper hand in navigating and conquering foreign territories, further fueling their imperialistic ambitions.

To understand the reasons behind the aggressive imperialism of this era, it's important to delve into historical documents, books, articles, and scholarly research that explore primary and secondary sources. This will provide a well-rounded understanding of the context, motives, and specific events driving the imperialist ventures of the industrialized nations between 1880 and 1914.