Arenac County is a county in the U.S. state of Michigan. As of the 2000 census, the population was 17,269. The county seat is Standish.

Arenac County was organized in 1883 and the name Arenac, coined by Henry Schoolcraft, is a derivation of the Latin "arena" and the Native American "ac". The combined words mean “sandy place.”

As of the 2000 census, there were 17,269 people, 6,710 households, and 4,717 families residing in the county. The population density was 47 people per square mile (18/km²). There were 9,563 housing units at an average density of 26 per square mile (10/km²). The racial makeup of the county was 95.38% White, 1.82% Black or African American, 0.95% Native American, 0.29% Asian, 0.01% Pacific Islander, 0.21% from other races, and 1.33% from two or more races. 1.38% of the population were Hispanic or Latino of any race. 24.0% were of German, 14.1% Polish, 11.6% French, 10.6% American, 7.9% English, 6.8% Irish and 5.3% French Canadian ancestry according to Census 2000. 96.9% spoke English and 1.3% Spanish as their first language.

Michigan (ⁱ/ˈmɪʃɨɡən/) is a state located in the Great Lakes region of the Midwestern United States. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake". Michigan is the 8th most populous of the 50 United States, with the 11th most extensive total area. Its capital is Lansing, and the largest city is Detroit. Michigan was admitted into the Union on January 26, 1837 as the 26th state.

Michigan has the longest freshwater coastline of any political subdivision in the world, being bounded by four of the five Great Lakes, plus Lake Saint Clair. Michigan is one of the leading U.S. states for recreational boating. The state has 64,980 inland lakes and ponds. A person in the state is never more than six miles (9.7 km) from a natural water source or more than 85 miles (137 km) from a Great Lakes shoreline. It is the largest state by total area east of the Mississippi River.

Michigan is the only state to consist of two peninsulas. The Lower Peninsula, to which the name Michigan was originally applied, is often noted to be shaped like a mitten. The Upper Peninsula (often referred to as "the U.P.") is separated from the Lower Peninsula by the Straits of Mackinac, a five-mile (8 km) channel that joins Lake Huron to Lake Michigan. The two peninsulas are connected by the Mackinac Bridge. The Upper Peninsula is economically important due to its status as a tourist destination. There is also a variety of natural resources to be found there, including a sizable amount of iron ore.