Unsupported Context Type when creating Controller

New to .net unsure what I am doing wrong here. I created a c# API project and then used ADO.Net entity mappings. Which looks like it created correct .cs files for the models based on all of my tables. I guess the next step is to create a controller, but I get an error message when that happens.

Model 1

namespace GoogleMapsAPIv1.Models
{
    using System;
    using System.Collections.Generic;

    public partial class Table1
    {
        public string COUNTRY_ID { get; set; }
        public string PROVINCE_ID { get; set; }
        public string CITY { get; set; }
        public string COUNTY { get; set; }
        public string POSTAL_CODE { get; set; }
        public Nullable<decimal> LATITUDE { get; set; }
        public Nullable<decimal> LONGITUDE { get; set; }
        public Nullable<decimal> DISTANCE_CACHED { get; set; }
        public string FIPS_PROVINCE_CODE { get; set; }
        public string FIPS_COUNTY_CODE { get; set; }
        public Nullable<System.DateTime> CREATED_DATE { get; set; }
        public Nullable<System.DateTime> LAST_MODIFIED_DATE { get; set; }
        public string SPATIAL_DATA { get; set; }
        public string TIMEZONE_ID { get; set; }
        public Nullable<int> GMT_OFF_SET { get; set; }
        public string SPATIAL_BOUNDARY { get; set; }
        public int DK_COUNTRY_ID { get; set; }
    }
}

The error message I get when I set this model as the Model Class and the Data Context class is

Unsupported Context Type 

The template I was using is API controller with read/write actions, using Entity framework