Good shots. Love the 1 of him peaking through the fence. I'm not a dog expert but, I have to disagree with your call of Leonberger. The color is wrong. I'm inclined to think Oreo is an old gentleman Newfie. Great dogs. A former neighbor had 1 appropriately named Bear. BTW Leonbergers are named for the town of Leonberg in Baden-Wurttemburg, Germany. The male is built like a Newfie. The female is slender, lighter in weight, & slightly shorter in height.
Oreo was saved from a shelter , must have been abused because for a long time he wouldn't let anyone pet him. He would just run away turn and bark. Thanks for looking and your reply.