Prior to the establishment of a Catholic mission and Spanish government in the Marianas, there was no western calendar in the Marianas as we have today. We're not even sure if our ancestors marked the passing of an old year and how many past years had gone by.
But when the Marianas did enter western time-keeping, the Marianas were on the eastern side of the Date Line, as can be seen in the German map of the Date Line above.
Notice that the Philippines was also on the eastern side of the Date Line in the map, and that explains it all.
When both the Marianas and the Philippines first came under Spanish rule, power flowed from Spain then to Mexico and then to the Marianas/Philippines. Since Mexico is east of the Date Line, so were the Philippines and the Marianas.
But then Mexico became independent of Spain in 1821 and contact between Mexico and the Philippines/Marianas dwindled to barely anything.
NARCISO CLAVERIA
Governor-General of the Philippines in 1844
The Spanish Governor-General of the Philippines, Narciso Claveria, decided to place the Philippines and the Marianas (which were under his authority) on the Asian, or western, side of the Date Line since our islands had more contact with Asia now.
NEWSPAPER ARTICLE FROM 1899 EXPLAINS THE STORY
In order to achieve this, Claveria decided that December 31, 1844 would not exist on the calendar. December 30, 1844 would be immediately followed by January 1, 1845 and the Philippines and Marianas would now be one day ahead of Mexico, the United States and Hawaii.
So, December 31, 1844, or New Year's Eve that year, never happened in the Marianas.