Osaka Higashi Line

Most of the line — the section between Kanzakigawa Signal Box and Kyūhōji — is a converted freight route. It was originally the Jōtō Freight Line, a freight branch of the Katamachi Line, and its passenger conversion had been envisaged since around the 1950s. In 1958 the Urban Transport Council's Report No. 3 took up, at the strong request of the Governor of Osaka, a plan to carry passengers over a corridor from Amagasaki via Suita, Hanaten, Kami and Sugimotochō toward Osaka's southern port district. After the value of a connection to the new Tōkaidō Shinkansen was recognised, the plan was revised in March 1963 to build a new line between Shin-Ōsaka and Awaji, and the Shin-Ōsaka–Kami–Sugimotochō stretch was incorporated into the Council's Report No. 7.

Through the Japanese National Railways (JNR) era the project languished, since a line skirting the city centre was not expected to draw heavy passenger traffic and JNR's finances were strained; there was also little organised local campaigning for it. After through-running of Hanwa Line and Kisei Main Line trains onto the Osaka Loop Line began in 1989 and a plan emerged for the "Naniwasuji Line" linking Shin-Ōsaka with JR-Namba and Shiomibashi, the southern terminus was changed to Kami (later Kyūhōji) and the link toward the Hanwa Line was dropped. In the 1996 government budget the scheme was adopted for third-sector subsidy, and in November 1996 the Osaka Soto-Kanjo Railway was founded by Osaka Prefecture, the cities along the route and JR West to build and own the line under vertical separation; it obtained its railway business licence that December and construction finally began.

The freight history of the corridor reaches back to the prewar period. On 15 March 1929 the Katamachi Line freight branch opened between Yodogawa, Tatsumi Signal Box and Suita — the date the Railway Directory (Tetsudō Yōran) records as the line's opening — and further freight sections followed: Hanaten–Hirano and Hanaten–Shigino–Tatsumi–Suita in 1931, and Hanaten–Yao in 1939. The Yodogawa–Tatsumi–Suita section closed in 1982. At the privatisation of JNR on 1 April 1987 JR West succeeded to the line as a Category 1 operator and JR Freight became a Category 2 operator.

The modern passenger project advanced in stages. Construction of the southern segment (Hanaten–Kyūhōji) was authorised in 1999 and begun that June; the northern segment (Shin-Ōsaka–Miyakojima) was authorised in 2002. On 23 August 2007 the line was given the name "Osaka Higashi Line," replacing the working title "Osaka Outer Loop Line" (大阪外環状線). After trial running began at the end of 2007, the southern section between Hanaten and Kyūhōji opened to passengers on 15 March 2008, and a "Direct Rapid" service was introduced running through to Amagasaki via the Katamachi and JR Tōzai lines, worked at first by 223-6000 series trains.

The northern section was far harder to finish. Originally targeted for completion in fiscal 2006, then 2012, it was repeatedly delayed by difficulties acquiring land and by a notorious never-opening level crossing near Higashi-Yodogawa Station. The route was redesigned so that trains would use the Tōkaidō Main Line branch (Umeda Freight Line) out of Shin-Ōsaka before diverging north of Higashi-Yodogawa toward Minami-Suita. Construction of the northern segment restarted in January 2011, an intermediate station (Kizuri-Kamikita) opened in 2018, and the Shin-Ōsaka–Hanaten section finally opened on 16 March 2019, completing the through line; the Direct Rapid was rerouted to run between Nara and Shin-Ōsaka. JR West noted that this was its first new passenger-line opening in the eleven years since the JR Tōzai Line.

The final piece was the extension into central Osaka. As the second phase of the project, underground platforms were built at Ōsaka Station in the redeveloping Umekita district, and from 18 March 2023 all Osaka Higashi Line trains began running through from Shin-Ōsaka via the Umeda Freight Line to those platforms, with the Direct Rapid now linking Ōsaka with Nara via the Yamatoji Line. The project also provides the basis for the future Naniwasuji Line and a shortcut for the Haruka and Kuroshio limited expresses. A limited express, the Mahoroba, began as a seasonal Shin-Ōsaka–Nara service in 2019 and became a regular weekend-and-holiday train in March 2025, giving the once freight-only corridor a full role in the region's passenger network.

• 192915 March: the Katamachi Line freight branch opens between Yodogawa, Tatsumi Signal Box and Suita — the date the Railway Directory records as the line's opening.
• 193110 August: the Hanaten–Hirano and Hanaten–Shigino–Tatsumi–Suita freight sections open (freight only).
• 193915 October: the Hanaten–Yao freight section opens (freight only).
• 198215 November: the Yodogawa–Tatsumi–Suita section is closed and Tatsumi Signal Box is abolished.
• 19871 April: at the privatisation of Japanese National Railways, JR West succeeds to the line as a Category 1 operator and JR Freight becomes a Category 2 operator.
• 199621 November: the Osaka Soto-Kanjo Railway is founded; on 25 December it obtains its railway business licence.
• 199917 February: construction of the (provisionally named) Osaka Outer Loop Line is authorised for the Miyakojima–Kyūhōji section; construction of the Hanaten–Kyūhōji southern segment begins that June.
• 200220 December: construction of the Shin-Ōsaka–Miyakojima northern section is authorised.
• 200723 August: the line is given the name 'Osaka Higashi Line,' replacing the working title 'Osaka Outer Loop Line,' and the new station names are decided; trial running on the southern section begins on 29 December.
• 200815 March: the southern section between Hanaten and Kyūhōji (9.2 km) opens to passengers as the Osaka Higashi Line; a Direct Rapid service to Amagasaki via the Katamachi and JR Tōzai lines begins, worked by 223-6000 series trains.
• 201111 March: the Direct Rapid is re-equipped from 223 series to 4-door 207 series trains; daytime services are standardised at 15-minute intervals the next day.
• 201817 March: Kizuri-Kamikita Station opens on the northern segment and station numbering is introduced across the line; the 103 series had ended service that January.
• 201916 March: the Shin-Ōsaka–Hanaten northern section opens, completing the through line; the Direct Rapid is rerouted to run between Nara and Shin-Ōsaka, with Takaida-Chūō and JR Kawachi-Eiwa added as stops. The seasonal limited express Mahoroba (Shin-Ōsaka–Nara) starts on 2 November.
• 202318 March: underground platforms open at Ōsaka Station (Umekita) and all trains begin running through from Shin-Ōsaka to Ōsaka via the Umeda Freight Line; the Direct Rapid, now Ōsaka–Nara via the Yamatoji Line, is re-equipped with 8-car 221 series trains and JR-Awaji is added as a stop.