 What most people do not know, however, is that the “coastal Pacific Northwest [has] become increasingly intertwined with the inland region providing significant support to the coast.”  Mainly agricultural Eastern Washington provides support to the coastal regions, by giving them “hydroelectric power, aluminum production for the airplane industry, and food to feed the ever-expanding population”.  Though during the last century the economy of Eastern Washington has diversified, the backbone is still agriculture.  Kay F. Reinartz explains in The Inland Northwest that “there is more to the [division between Western and Eastern Washington] than economics, but economics makes it strong[er].” 
These economic differences, coupled with different climates, have created two very different areas within one political boundary.  The division of Western and Eastern Washington are commonly referred to as the “Cascade Curtain,” as the Cascade Mountain range divides the two regions of Washington.  It has been the development in each region, along with the end of settlement that has allowed the proverbial Cascade Curtain to spring up.  The understanding of how two such diverse regions were placed in one political boundary is essential to understanding the political division within the State of Washington.  The first settlers who migrated to what would become Washington State were largely composed of settlers from the Mid-Western part of the United States.  
When the Washington Territory was carved out of the Oregon Territory in 1853, it contained only a few thousand settlers along with a few missionaries and employees of the Hudson’s Bay Company scattered though what today is the entirety of Washington, Idaho, and portions of Montana and Wyoming.  Though later there would be influxes of largely foreign settlers in the latter part of the 19th Century, the population of Washington was very dynamic in number until the 20th Century.  
Early population booms with the discoveries of precious metals brought the first real settlements to what would become Eastern Washington, along with modern Idaho as well, during the mid-19th Century.  This allowed for the first East-West conflict, as the territorial capital of Olympia, which today remains the capital of Washington State fought to hold on the power it had as territorial capital.  This conflict created the boundaries of Washington that can be seen today.  Those who migrated east of the Cascades expressed dissatisfaction with the territorial government of Washington, and called for a territory to be created out of modern Eastern Washington and Idaho, along with parts of Montana and Wyoming.  Many population centers vied to be made capital of the Washington territory, yet the capital remained in Olympia. 
Washington’s boundaries were sealed at their modern limits, with Olympia keeping enough territory so it could keep a large amount of land while keeping the most population, and thus most power in the territorial government.  Indeed, we see that such struggles for power in Washington are not only a modern occurrence but today mirror the old struggles of the 19th century. 