The Western Cordillera, a vast mountain range that stretches along the western edge of North and South America, was not "made" in a single era. It's a complex geological feature that formed over millions of years, through a series of tectonic processes and events.

Here's a breakdown of the key eras and events involved:

* Precambrian Era (4.5 billion to 541 million years ago): The formation of the North American and South American continents began during this era.

* Paleozoic Era (541 to 252 million years ago): The continents collided and fragmented multiple times, contributing to the initial uplift of the Western Cordillera.

* Mesozoic Era (252 to 66 million years ago): The breakup of Pangaea, the supercontinent, and the opening of the Pacific Ocean led to the formation of the subduction zone along the west coast of the Americas. This is where the Pacific Plate began to slide beneath the continental plates, leading to significant volcanic activity and mountain building.

* Cenozoic Era (66 million years ago to present): The subduction process continued, leading to the uplift of the Western Cordillera to its present-day height. This era also saw the formation of the Rocky Mountains, the Sierra Nevada, the Andes, and other major ranges within the Western Cordillera.

It's important to note:

* The Western Cordillera is still being formed today. The ongoing subduction process continues to reshape the mountains, causing earthquakes, volcanic eruptions, and other geological activity.

* The specific timing and processes vary across the different regions within the Western Cordillera. Different mountain ranges within the cordillera have different ages and formation histories.

So, while the Western Cordillera has roots deep in the Precambrian era, it was shaped and reshaped throughout geological time, particularly during the Mesozoic and Cenozoic eras.