Wash the spinach and drain well.
Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add the spinach (in batches if needed) and cook, stirring, until just wilted, 3–5 minutes. Transfer to a bowl to cool, then squeeze out excess liquid and roughly chop the wilted spinach.
Peel and finely dice the onion and garlic. Do not rinse the Arborio rice (you want the starch for creaminess).
Drain and rinse the canned chickpeas. Slice the olives.
In a medium pot or Dutch oven, heat the remaining 1 1/2 tablespoons olive oil over medium heat. Add the diced onion and garlic and cook, stirring occasionally, until softened, 4–5 minutes.
Add the 1/2 cup Arborio rice and stir 1–2 minutes to coat the grains with oil and lightly toast.
Stir in the chopped cooked spinach and the dried herbs (1/2 tsp thyme, 1/2 tsp rosemary, 1/2 tsp sage). Pour in 1 1/3 cups vegetable broth and bring to a boil.
Reduce heat to low, cover, and simmer until the rice is tender, about 15 minutes. Check after 10 minutes to confirm the rice is cooking through and not sticking; continue simmering, covered, until tender.
When the rice is tender, remove the pot from the heat. Stir in the drained chickpeas and sliced olives until evenly combined. Let the pot sit, covered, 2–3 minutes to warm the chickpeas and meld flavors.
Fluff gently and serve warm.