EU9, has grown to be an integral part of the EU. This group entered the EU in its 3rd expansion phase in 2004, injecting diversity and fresh perspectives into the Union's mix.

The EU9 countries include Hungary, Slovenia, Latvia, Lithuania, Poland, Estonia, Slovakia, Czech Republic, and Malta. These countries each have given substantial contributions towards enhancing the aims of the European Union.

Therefore, grasping the function EU9 holds in the European Union is necessary for any study relating to European economics, politics, or international relations.

Right from their admission, the members of EU9 have read more contributed significantly towards shaping the policies of the European Union. Their geographical location offers critical strategic edges, making them a considerable part of the EU's defense and security strategies.

Additionally, these nations have significantly contributed to the European Union's financial strength. The EU9's rapid economic growth and keen integration into the EU market has created increased trade with other EU members.

The social contribution of the EU9 is equally significant. These countries introduce profound historical backgrounds, individual cultural practices, and diverse languages, thus enhancing the diversity of the EU.

The inclusion of EU9 has also affected the political dynamics within the EU. With their involvement, the power dynamics have altered, with new coalitions and alliances forming.

In conclusion, the parts played by the EU9 members are significant. From economic influence to cultural richness, and from security strategies to political dynamics, EU9 has robustly augmented the European Union's core strength. As such, an in-depth understanding of the EU9 is crucial to fully grasping the subtleties of the European Union.