How to access the values in nested dictionary sent to django template

Question

I'm sending a nested custom dictionary through my views, that nested dictionary is 'history'

def update_participation(request,user_id,event_id):
    ev=Event.objects.get(id=event_id)
    data=Participated(user=user_id,event=event_id)
    data.save()
    participated=Participated.objects.filter(user=user_id)
    i=0

    #Declared the dictionary history
    history={}

    #Adding values to dictionary
    for partcipate in participated:
        name=Event.objects.get(id=partcipate.event)
        name1=name.name
        fest=Fest.objects.get(id=name.fest_id.id)
        fest1=fest.name
        clg=College.objects.get(id=fest.clg_id.id).name
        history[i]={'event':name1,'fest':fest1,'college':clg}
        i+=1
    messages.success(request,f'You have registered for {ev.name}')

    #sending the dictionary to template
    return render(request,'webpage/my_events.html',history)

Example of dictionary will look

history={0={'event':'css battle','fest':'verve','college':'jss'},
         1={'event':'code wars','fest':'verve','college':'jss'},
         2={'event':'hangman','fest':'phase shift','college':'bms'}}

I'm trying to access the values css battle, verve, jss like

{%extends 'webpage/base.html'%}
{%block content%}
<h2 style="margin:5px 30px;"><u>My Event History</u></h2>
<div style="margin:50px 0px 0px 270px" class='table'>
    <table border='5'>
        <tr>
            <th>Event</th>
            <th>Fest</th>
            <th>College</th>
        </tr>
        {%for key,value in history.items%}
            <tr>
                <td>{{value.event}}</td>
                <td>{{value.fest}}</td>
                <td>{{value.college}}</td>
            </tr>
        {%endfor%}
    </table>
</div>
{%endblock content%}

How am I supposed to iterate through the dictionary?