The National League West is Just One of the three Branches of the National League of Major League Baseball in North America (including Canada).

This Division was formed for the 1969 season when the National League expanded to 12 teams by incorporating the San Diego Padres and the Montreal Expos. For purpose of keeping a regular-season of all 162 games, half of those teams were put into the new East Division and half to the new West Division. Within each division, the teams played 18 games each against their five division mates (90 matches ), and also 12 games against the teams in the opposite division (72 matches ), totaling 162 games.
Despite the geography, the owners of the Chicago Cubs insisted that their staff be put into the East Division along with the teams at New York City, Philadelphia, and Pittsburgh. Also, the owners of the St. Louis Cardinals wanted that team to be in the exact same branch with their natural competitions of the Cubs. Like the American League did, the league might have insisted on a orientation. But the owners were concerned about what they thought would be a massive imbalance in the strength of these divisions. From the two seasons prior to realignment, the Cardinals, Giants, and Cubs finished 1-2-3 in the National League standings. The owners were worried about putting those teams in exactly the same division, thereby producing one very powerful division (West) and one weak one (East). Given All This, the owners of the Atlanta Braves and the Cincinnati Reds consented to being placed into the West Division, although Atlanta and Cincinnati are both from the Eastern Time Zone. Consequently , the West Division had teams spread all of the way from the East to the Pacific Coast, and scattered over four time zones. The East Division was spread across the Eastern Time Zone and the Central Time Zone – in Spite of the Fact that the National League had six teams in the Eastern Time Zone and six teams spread between the Central Time Zone and the Pacific Time Zone.
All this increased the traveling distances and times for all the teams, and it also made radio broadcasting and TV broadcasts of those games more challenging to schedule. The Braves and the Reds needed to travel all of the way to California three times during every baseball season, along with the three groups in California needed to travel to Atlanta, Cincinnati, and Houston three times also. From time to time, the trouble could be alleviated to get them by playing a few games in Chicago, St. Louis, or Pittsburgh on the same long road trips. The 1994 addition of the Central Division would completely remedy these problems, when the Reds and Braves moved into the NL Central and NL East respectively.

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