Here's a start. I saved the picture you posted as "image.png". You may have to adjust the fig.Position vector to size it correctly. You also might want to select a picture that doesn't have a black background.
fig = figure;
ax = axes(fig);
img = imread('image.png');
yLimits = [0 1000]; %you can make this your longitude
xLimits = [0 500]; %you can make this your latitude
image('CData',img,'XData',xLimits,'YData',flip(yLimits))
hold on
x = randi(xLimits,10,20); %some random x data
y = randi(yLimits,10,20); %some random y data
p = scatter(x,y,'ro','filled');
hold off
axis tight
