Command Parameter needs to be turned into Enum

I am learning WPF and MVVM again. I have an application in which I pass a command with a parameter that as I understand can only be turned into a string? I need to somehow turn that string into an enum value. What can I do?

As part of my model, a class that contains an array of another model object, each with a name property. The array was created using the values of the enumeration as indices. Basically, I have a year composed of months and those months are to contain financial data.

   /// <summary>
   /// Months in a year
   /// </summary>
   public enum Month
   {
      January,
      February,
      March,
      April,
      May,
      June,
      July,
      August,
      September,
      October,
      November,
      December
   };

...

   //------------------------------------------------------------------------------
   public class FinancialYear
   {
      FinancialMonth[] m_financialMonths;

      /// <summary>
      /// Constructor
      /// </summary>
      /// <param name="year"></param>
      public FinancialYear(int year)
      {
         if (year < 1900 || year > 9999)
         {
            throw new ArgumentException("Year argument must be between 1900 and 9999 inclusive.");
         }
         Year = year;

         string[] monthNames = Enum.GetNames(typeof(Month));
         int numberOfMonths  = monthNames.Length;

         m_financialMonths    = new FinancialMonth[numberOfMonths];

         for (int index = 0; index < numberOfMonths; ++index)
         {
            m_financialMonths[index] = new FinancialMonth(monthNames[index]);
         }
      }

...

Now my problem is that I have a collection of view models in my main window view model and want to navigate to them using a number of buttons that I have created. How do I pass "which month" from the view to the viewmodel since I really am looking for an enum type? What goes in the below?

<Button x:Name="btnJan" Content="Jan" Command="{Binding ChangeContentCommand}" CommandParameter="January" Style="{StaticResource NavButton}" Margin="2,2,2,2" Padding="8,4,8,4"/>
            <Button x:Name="btnFeb" Content="Feb" Command="{Binding ChangeContentCommand}" CommandParameter="February"Style="{StaticResource NavButton}" Margin="2,2,2,2" Padding="8,4,8,4"/>

etc. etc.           

      // <summary>
      /// Method executed by the ChangeContentCommand
      /// </summary>
      /// <param name="parameter">Optional parameter send with the command</param>
      private void ChangeContent(object parameter)
      {
         if (parameter != null)
         {
            string commandParam = parameter.ToString();
         }
      }

Edit:

The question could be simply: How do I convert a string to an enum value. But, I'd also like input on whether or not I should be using an enum this way at all, if some other collection would be better suited, if I am just way off base on how I am doing this or not, etc. I come from C++ so this use of an enumeration seems natural to me, but it seems .NET enums are somewhat different.