React webpack.config.js

.babelrc

{
    "presets": [
        "es2015",
        "react"
    ]
}

package.json

"dependencies": {
  "react": "15.0.1",
  "react-dom": "15.0.1",
  "react-router": "2.4.0"
},
"devDependencies": {
  "babel-core": "6.7.7",
  "babel-loader": "6.2.4",
  "babel-preset-es2015": "6.6.0",
  "babel-preset-react": "6.5.0",
  "webpack": "1.13.0",
  "webpack-dev-server": "1.14.1",
  "html-webpack-plugin": "*"
}

webpack.config.js

var HtmlWebpackPlugin = require('html-webpack-plugin')
var HTMLWebpackPluginConfig = new HtmlWebpackPlugin({
  template: __dirname + '/app/index.html',
  filename: 'index.html',
  inject: 'body'
});
module.exports = {
  entry: [
    './app/index.js'
  ],
  module: {
    loaders: [
      {test: /\.js/, exclude: /node_modules/, loader: "babel"}
    ]
  },
  output: {
    filename: "index_bundle.js",
    path: __dirname + '/dist'
  },
  plugins: [HTMLWebpackPluginConfig]
};