The period between 1830-1848 is referred …

During the time period from 1830 to 1848 many revolutions took place because since the conservative relation after 1815 many monarchichal and despotic regimes were reestablished all over Europe. However, the ideals of nationalism, republicanism and liberalism had already been instilled in the people of Europe. This led to a major churning of nationalist aspirations among the multi-lingual and multi-ethnic states of Europe. Different nations started to demand thier own states with republican rule. This led to many insurrections against the monarchical and conservative rule all over Europe between 1830 to 1848.
For instance,

1. The first upheaval took place in France in July 1830. The Bourbon kings who had been restored to power during the conservative reaction after 1815, were now overthrown by liberal revolutionaries who installed a constitutional monarchy with Louis Philippe at its head.
2. The Greek war of Independence that started in 1821. Nationalists in Greece got support from other Greeks living in exile and also from many West Europeans who had sympathies for ancient Greek culture. Finally, Greece gained its independence in 1832 after the Treaty of Constantinople recognised Greece as one.