North Dakota and South Dakota were both part of the Dakota Territory. The Dakota Territory was split into the states of North Dakota and South Dakota when President Benjamin Harrison signed proclamations in Washington, DC, on November 2, 1889, formally admitting both North Dakota and South Dakota to the union. President Harrison had the papers shuffled so that no one would know which proclamation was signed first.
It is an analogy. North Carolina is to South Carolina as North Dakota is to South Dakota.
North Dakota is north of South Dakota.
The US state of North Dakota is north of South Dakota.
North Dakota is up by the border of Canada, Wyoming is just next to South Dakota.
North Dakota is to South Dakota as North Carolina is to South Carolina.
Saskatchewan and Manitoba, Canada are to the north of North Dakota and North Dakota is to the north of South Dakota.
The US state of South Dakota is south of the US state of North Dakota.
At the same time South Dakota became a state, North Dakota was also admitted into the union. So that the order of signing the proclamations would be unknown, the proclamations were mixed up and South Dakota and North Dakota were admitted as the 39th and 40th states. Since that time, North Dakota has been alphabetically listed first, as the 39th US state, and South Dakota listed as the 40th US State.
North Dakota South Dakota North Carolina South Carolina
The state of North Dakota is north (or above) the state of South Dakota.
The state of South Dakota is south of North Dakota.
North Dakota is bordered by South Dakota to the south.