MVC5 Validations

I have added several attributes to a property of a Model class. Some of the attributes work (e.g. DisplayName) but some atributes dont work (e.g. Required). 

Here is the model class:

public classLoginModel

    {

        [Required]

        [Display(Name = "User Name or Email")]

       publicstring UserName { get;set; }

        [Required]

        [DataType(DataType.Password)]

        [Display(Name = "Password")]

       publicstring Password { get;set; }

    }

Here is the View razor code:

<div>

   @Html.LabelFor(m => m.UserName)

</div>

<div>

@Html.EditorFor(m => m.UserName)

@Html.ValidationMessageFor(m => m.UserName)

</div>

Here is the Html generated from the View:

<div>                                        

<labelfor="UserName">User Name or Email</label>                            

</div>

<div>                             

<inputclass="text-box single-line"data-val="true"data-val-required="The User Name or Email field is required."id="UserName"name="UserName"type="text"value=""/>

<spanclass="field-validation-valid"data-valmsg-for="UserName"data-valmsg-replace="true"></span>

</div>

When I run the app the Required validation does no work.  The Model.IsValid is always true.

I have the proper steeings in the web,config

Any idea of why the Required validation wont work would be apprciated.

PS I have tried adding other attributes like StringLength and they dont work either